Space

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[Sean Robinson]

I figured there needed to be a “Space” thread.
If the mods think it should be rolled into the Science thread, I have no problem with that.
If it’s the “nutjobs” this thread seems to pull in you’re worried about, just double-up on the tinfoil hat
_______________________
The following has been debunked. see post #9 on Dec.14th)
Toldya about the tinfoil hat…
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– Scientists Just Found an “Impossible” Black Hole in The Milky Way Galaxy
– A newfound black hole in the Milky Way is weirdly heavy
– Monster black hole that ‘should not exist’ discovered in the Milky Way

The chemical composition of our galaxy’s most massive stars suggests that they lose most of their mass at the end of their lives through explosions and powerful stellar winds, before the star’s core collapses into a black hole.

The hefty stars in the mass range that could produce a black hole are expected to end their lives in what is called a pair-instability supernova that completely obliterates the stellar core. So astronomers are scratching their heads trying to figure out how the black hole – named LB-1 – got so chonky.

“Black holes of such mass should not even exist in our galaxy, according to most of the current models of stellar evolution,” said astronomer Jifeng Liu of the National Astronomical Observatory of China.

“LB-1 is twice as massive as what we thought possible. Now theorists will have to take up the challenge of explaining its formation.”

• This topic was modified 4 years, 4 months ago by Sean Robinson.
• This topic was modified 4 years, 2 months ago by Sean Robinson.
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‘Bumblebee gravity’ could explain why the universe is expanding so quickly

Bumblebee gravity could be proven true if scientists find that a black hole’s shadow is smaller than existing physics theories would predict.

Physicists have long assumed that the universe is pretty much the same in any direction, and now they’ve found a new way to test that hypothesis: by examining the shadow of a black hole.

If that shadow is a wee bit smaller than existing physics theories predict, it could help prove a far-out notion called bumblebee gravity, which describes what would happen if the seemingly perfect symmetry of the universe isn’t so perfect after all.

If scientists can find a black hole with such an undersized shadow, it would open the door to a brand-new understanding of gravity — and perhaps explain why the universe is expanding ever faster.

But to understand how this bumblebee idea could fly, let’s dig into some fundamental physics.

Looking in the mirror

Physicists love symmetry; after all, it helps us understand some of the deepest secrets of the universe. For example, physicists have realized that if you conduct an experiment on fundamental physics you can move your testing equipment somewhere else and you’ll get the same result again (that is, if all other factors, like the temperature and the strength of gravity, remain the same).

In other words, no matter where in space you conduct your experiment, you’ll get the same result. Through mathematical logic, this leads directly to the law of conservation of momentum.

Another example: If you run your experiment and wait awhile before running it again, you’ll get the same result (again, all else being equal). This temporal symmetry leads directly to the law of conservation of energy — that energy can never be created nor destroyed.

There’s another important symmetry that forms a bedrock of modern physics. It’s called the “Lorentz” symmetry, in honor of Hendrik Lorentz, the physicist who figured all this out in the early 1900s. It turns out that you can take your experiment and turn it, and (all else being equal) you will get the same result. You can also boost your experiment to a fixed velocity and still get the same result.

In other words, all else being equal — and yes, I’m repeating that often, because it’s important — if you’re conducting an experiment at total rest, and doing the same experiment at half the speed of light, you’ll get the same result.

This is the symmetry that Lorentz uncovered: The laws of physics are the same regardless of position, time, orientation and speed.

What do we get out of this fundamental symmetry? Well, for starters, we get Einstein’s entire theory of special relativity, which sets out a constant speed of light and explains how space and time are linked for objects traveling at different speeds.

Bumblebee gravity

Special relativity is so essential to physics that it’s almost a metatheory of physics: If you want to concoct your own idea of how the universe works, it has to be compatible with the dictates of special relativity.

Or not.

Physicists are constantly trying to cook up new and improved theories of physics, because the old ones, like general relativity, which describes how matter warps space-time and the Standard Model of particle physics, cannot explain everything in the universe, such as what happens at the heart of a black hole. And one very juicy place to look for new physics is to see if any cherished notions might not be so accurate in extreme conditions — cherished notions like Lorentz symmetry.

Some models of gravity argue that the universe isn’t exactly symmetrical after all. These models predict that there are extra ingredients in the universe that force it to not exactly obey Lorentz symmetry all the time. In other words, there would be a special, or privileged, direction in the cosmos.

These new models describe a hypothesis dubbed “bumblebee gravity.” It gets its name from the supposed idea that scientists once claimed that bumblebees shouldn’t be able to fly, because we didn’t understand how their wings generated lift. (Scientists never actually believed that, by the way.) We don’t fully understand how these models of gravity work and how they could be compatible with the universe that we see, and yet, there they are, staring us in the face as viable options for new physics.

One of the most powerful uses of bumblebee gravity models is to potentially explain dark energy —the phenomenon responsible for the observed accelerated expansion of the universe. It turns out that the degree to which our universe violates Lorentz symmetry can be tied to an effect that generates accelerated expansion. And because we have no idea what’s creating dark energy, this possibility looks very appealing indeed.

The black shadow

It took eight telescopes and more than 200 astronomers to produce an astonishing, never-before-seen image of a distant black hole. The dark circle at the center is the black hole’s shadow.

So you have a buzzy new theory of gravity based on some icon-smashing ideas like symmetry violation. Where would you go to test that idea? You’d go to the place where gravity is stretched to the absolute limit: a black hole. In the new study, not yet peer-reviewed and published online in November 2020 to the preprint database arXiv, researchers did just that, looking at the shadow of a black hole in a hypothetical universe modeled to be as realistic as possible.

(Remember that first-ever image of black hole M87, produced by the Event Horizon Telescope just a year ago? That hauntingly beautiful, dark void in the center of the bright ring was actually the black hole’s “shadow,” the region that sucked in all of the light from behind and around it.)

To make the model as realistic as possible, the team placed a black hole in the background of a universe that was accelerating in its expansion (exactly like what we observe) and tuned the level of symmetry violation to match the behavior of dark energy that scientists measure.

They found that, in this case, a black hole’s shadow can appear up to 10% smaller than it would in a “normal-gravity” world, providing a clear way to test bumblebee gravity. While the current image of black hole M87 is too fuzzy to tell the difference, efforts are underway to take even better pictures of more black holes, probing some of the deepest mysteries of the universe in the process.

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Todd

[Sean Robinson]

Entire collection? Oh, please.
Not sure what they’re up to, but I’m a little busy making a tinfoil bodysuit (with a mask).
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CIA releases entire collection of UFO-related documents to truth-seeking website

The ‘Black Vault’ documents cover everything from mysterious Russian explosions to top government officials being hand-delivered UFO intel.

U.S. Navy videos of alleged UFO sightings were declassified in 2020.

More than three decades’ worth of government UFO records are now yours to download and peruse, thanks to the efforts of some intrepid truth-seekers.

The massive data dump includes more than 2,700 pages of UFO-related documents declassified by the CIA since the 1980s. (The U.S. government also calls them “unidentified aerial phenomena, or UAP). According to The Black Vault — an online repository of UFO-related documents operated by author John Greenwald Jr. — the documents were obtained through a long string of Freedom of Information Act (FOIA) requests filed over the last quarter century .

Over time, so many requests piled up that the CIA created a CD-ROM full of declassified documents, known as “The UFO collection.” In mid-2020, Greenwald purchased the CD-ROM, and he recently finished uploading its contents as a series of searchable PDF files on his website. (You can find them at The Black Vault.)

The documents cover dozens of incidents, including the 1976 account of the government’s then-Assistant Deputy Director for Science & Technology being hand-delivered a mysterious piece of intelligence on a UFO, to the description of a mysterious midnight explosion in a small Russian town.

“Although the CIA claims this is their ‘entire’ [declassified] collection, there may be no way to entirely verify that,” Greenwald wrote in a statement on The Black Vault website. “Research by The Black Vault will continue to see if there are additional documents still uncovered within the CIA’s holdings.”

The data dump arrives months before officials from the U.S. Department of Defense and intelligence agencies are due to appear before Congress and spill their guts on everything they know about UFOs, the New York Post reported. A provision attached to the nearly 5,600-page COVID-29 relief bill passed in late December 2020 requires the agencies, “to submit a report within 180 days … to the congressional intelligence and armed services committees on unidentified aerial phenomena.”

Repository of sensitive government intelligence, or bootleg ‘X-Files’ DVD? This CD-ROM actually contains nearly 2,700 pages of declassified CIA documents, according to the Black Vault.

The provision follows a banner year for UFOs, when startling footage of an unidentified object darting around several U.S. Navy planes in 2004 and 2015 was finally declassified.

While the new data dump is significant, it’s also just a drop in the bucket of The Black Vault’s enormous archive. The website reportedly contains more than 2.2 million pages of UFO-related material in its archive, which Greenwald obtained through more than 10,000 FOIA requests. According to the Vault website, Greenwald filed his first FOIA request in 1996, when he was just 15 years old.

• This reply was modified 3 years, 11 months ago by Sean Robinson.

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Todd

A neutron-star crash spotted 3 years ago is still pumping out X-rays. But why?

An artist’s depiction of X-ray emissions forming the last afterglow of the high-energy jets produced by a neutron-star collision.

Three years ago, two neutron stars collided in a cataclysmic crash, the first such merger ever observed directly. Naturally, scientists kept their eye on it — and now, something strange is happening.

Astrophysicists observed the star collision on Aug. 17, 2017, spotting for the first time ever signs of the same event in both a gravitational-wave chirp detected by the Laser Interferometer Gravitational-Wave Observatory (LIGO) on Earth and a massive burst of different flavors of light. The X-rays observed at the location 130 million light-years from Earth peaked less than six months after the merger’s discovery, then began to fade. But in observations gathered this year, that trend has stopped, and an X-ray signal is unexpectedly lingering, according to research presented on Thursday (Jan. 14) at the 237th meeting of the American Astronomical Society, held virtually due to the pandemic.

“Our models so far were describing the observation incredibly well, so we thought we nailed it down,” Eleonora Troja, an astrophysicist at the University of Maryland and NASA’s Goddard Space Flight Center in Maryland, told Space.com. “I think everybody was convinced that this thing was going to fade quickly, and the last observation showed that it is not.”

A star crash checkup … and mystery

When NASA’s Chandra X-ray Observatory checked in on the former merger in the spring, things were beginning to look fishy. Scientists thought they were looking at the afterglow of the high-energy jet of material shot out by the collision, and they had expected the X-rays to have faded by the spring. But the source was still glowing in the spacecraft’s view. When the telescope looked again, in December, it still found a bright X-ray signal.

It’s too early to know what precisely is happening, Troja said. Chandra may not look again until this December, although she plans to ask for the telescope to change plans to check in sooner. Radio instruments can study the collision more frequently, and could help solve the puzzle between now and then.

For now, Troja believes one of two hypotheses will explain the continued X-ray emissions.

In one scenario, the lingering X-rays are joined by radio light within the next eight months or year. Troja said that would suggest that scientists are seeing not the afterglow of jets shooting out from the collision, but the afterglow of the massive kilonova explosion itself — something scientists have never seen before.

An artist’s depiction of a cloud of debris created by a neutron-star collision.

“People think that in the 21st century we have seen it all and there is no first time left,” she said. Not so if this hypothesis holds. “This would be a first, it would be a new type of light, a new form of astrophysical source that we have never seen before.”

If the X-ray emissions continue but no radio emissions join them, Troja thinks scientists may be looking at something perhaps still more intriguing: proof that the collision formed a massive neutron star, the most massive such object known to date.

Soon after the collision, scientists calculated the mass of the initial neutron stars and the mass of what was left, after the dramatics shot matter out into space. But that value is between the current largest known neutron star and the smallest known black hole, leaving scientists stumped. The new observations could decide it: If the object is emitting X-rays, it sure isn’t a black hole. Confirming the result of the collision would give scientists an opportunity to better understand how matter behaves in superdense neutron stars, she said.

“We have a beautiful problem,” Troja said. “No matter what the solution is, it’s going to be exciting, which is a great problem to have in astrophysics.”

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Now-dead radio telescope finds bizarre venomous-spider star

This thing has a bite.

Neutron stars are among the densest objects in the universe.

Astronomers have discovered black widows and redbacks in space. While these cosmic objects don’t kill and eat their mates, the stars share their eight-legged counterparts’ violent behavior toward companions.

In addition to the run-of-the-mill spider stars, the researchers also discovered a bizarre black widow-redback crossbreed. The scientists used the now-destroyed Arecibo telescope in Puerto Rico to discover the weirdo stars.

Spider stars are types of millisecond pulsars, or neutron stars that act like precise clocks in the sky, whirling around at least once every 30 milliseconds and flashing like a lighthouse with each rotation. Neutron stars, the tiny, compressed cores of old, exploded stars, often rip material from other stars locked in binary orbits with them and use the push of that infalling material to get up to pulsar speed. Spider stars are rare and special versions of these stars though: They orbit so close to their binary companions that they blast away their surfaces, inhaling vast amounts of material like a spider tearing its partner limb from limb.

In a new paper, researchers identify three new black widows and a redback in the Milky Way. They also found a spider star that defies categorization, almost like a crossbreed of the two species.

When a spider star has reduced its companion to significantly less than a tenth the mass of the sun (usually 0.02 to 0.03 times the sun’s mass), that star is called a black widow. Redbacks have heftier companions that boast more than a tenth of the sun’s mass. These binary companions of redbacks pass between the spider star and Earth periodically, creating temporary eclipses. The shriveled companions of black widows don’t typically pull off that trick.

The seeming crossbreed star is difficult to categorize. For now, researchers have labeled it a redback because its companion sometimes eclipses its ticking light. And that companion has a mass at least 0.055 times the mass of the sun (possibly larger), which would be quite heavy for a black widow, though quite light for a redback. For now, the exact mechanisms of that system are still a mystery.

Studies like this might get harder in the future. The paper, published Jan. 1 to the arXiv database, relied on data collected between 2013 and 2018 using the Arecibo 305-m radio telescope which has since collapsed, as Live Science reported.

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Humans could move to this floating asteroid belt colony in the next 15 years, astrophysicist says

Should we build a ‘megasatellite’ of human habitats around the dwarf planet Ceres? It’s more plausible than it sounds.

This NASA illustration depicts an O’Neill Cylinder: a floating human habitat orbiting an alien planet. A new paper proposes building a mega-colony of them around the dwarf planet, Ceres.

Now more than ever, space agencies and starry-eyed billionaires have their minds fixed on finding a new home for humanity beyond Earth’s orbit. Mars is an obvious candidate, given its relatively close proximity, 24-hour day/night cycle and CO2-rich atmosphere. However, there’s a school of spacefaring thought that suggests colonizing the surface of another planet — any planet — is more trouble than it’s worth.

Now, a new paper published Jan. 6 date to the preprint database arXiv offers a creative counter-proposal: Ditch the Red Planet, and build a gargantuan floating habitat around the dwarf planet Ceres, instead.

In the paper, which has not yet been peer-reviewed, astrophysicist Pekka Janhunen of the Finnish Meteorological Institute in Helsinki describes his vision of a “megasatellite” of thousands of cylindrical spacecrafts, all linked together inside a disk-shaped frame that permanently orbits Ceres — the largest object in the asteroid belt between Mars and Jupiter. Each of these cylindrical habitats could accommodate upwards of 50,000 people, support an artificial atmosphere and generate an Earth-like gravity through the centrifugal force of its own rotation, Janhunen wrote. (This general idea, first proposed in the 1970s, is known as an O’Neill cylinder).

But why Ceres? Its average distance from Earth is comparable to that of Mars, Janhunen wrote, making travel relatively easy — but the dwarf planet also has a big elemental advantage. Ceres is rich in nitrogen, which would be crucial in developing the orbiting settlement’s atmosphere, Janhunen said (Earth’s atmosphere is roughly 79% nitrogen.) Rather than building a colony on the surface of the tiny world — Ceres has a radius roughly 1/13th that of Earth — settlers could utilize space elevators to transfer raw materials from the planet directly up to their orbiting habitats.

This orbital lifestyle would also address one of the biggest caveats Janhunen sees in the idea of a Martian surface colony: the health impacts of low gravity.

“My concern is that children on a Mars settlement would not develop to healthy adults (in terms of muscles and bones) due to the too-low Martian gravity,” Janhunen told Live Science in an email. “Therefore, I searched for [an] alternative that would provide [Earth-like] gravity but also an interconnected world.”

Even so, Janhunen’s proposal comes with its own caveats that could work against a successful Ceres colony, an outside researcher pointed out.

This NASA illustration shows what the interior of an O’Neill Cylinder could look like. Each habitat would have an artificial atmosphere, Earth-like gravity and a mix of urban and agricultural space.

Welcome to disk-world

According to Janhunen’s proposal, each cylinder of the Ceres megasatellite would produce its own gravity through rotation; each cylindrical habitat would measure about 6.2 miles (10 kilometers) long, have a radius of 0.6 miles (1 km) and complete a full rotation every 66 seconds to generate the centrifugal force needed to simulate Earth-like gravity.

A single cylinder could comfortably hold about 57,000 people, Janhunen said, and would be held in place next to its neighboring cylinders through powerful magnets, like those used in magnetic levitation.

Janhunen’s megasatellite would include a disk of interconnected habitat cylinders (center), flanked on both sides by massive mirrors to angle sunlight into the colony.

That interconnectedness points to the other big advantage of megasatellite living, Janhunen said: New habitat cylinders could be added onto the edges of the colony indefinitely, allowing for near unlimited expansion.

“Mars’ surface area is smaller than Earth’s, and consequently it cannot provide room for significant population and economic expansion,” Janhunen told Live Science. A Ceres colony, on the other hand, “is growable from one to millions of habitats.”

Seeing the light

Beyond the cylinders and their massive disk frame, the colony’s main features will be two enormous glass mirrors, angled at 45 degrees relative to the disk in order to reflect just enough natural sunlight into each habitat. Part of each cylinder will be devoted to growing crops and trees, planted in a 5-foot-thick (1.5 meters) bed of soil derived from raw materials from Ceres, Janhunen wrote. The natural sunlight should keep them growing strong. (The “urban” part of each cylinder, meanwhile, would rely on artificial light to simulate an Earth-like day/night cycle. Janhunen does not stipulate where the settlement’s oxygen comes from.)

This society of floating, cylindrical utopias may sound a bit outlandish, but it has its proponents. In 2019, Jeff Bezos (Amazon CEO and founder of the private space company Blue Origin) spoke at a Washington, D.C., event about the merits of building “O’Neill colonies” similar to the one Janhunen describes here. Bezos was skeptical that such a colony could exist in our lifetime, asking the audience, “How are we going to build O’Neill colonies? I don’t know and no one in this room knows.”

However, Janhunen is more optimistic. In an email to Live Science, he said that the first human settlers could start heading to Ceres within the next 15 years.

The future is bright when you live in a habitat cylinder millions of miles from Earth.

Next year on Ceres?

Manasvi Lingam, an assistant professor of astrobiology at the Florida Institute of Technology who studies planet habitability, said that the Ceres proposal presents a “plausible alternative” to colonizing the surface of Mars or the Moon, but still lacks some key considerations.

“I would say there are three main caveats,” Lingam, who was not involved with the paper, told Live Science. “The first is a question of other essential elements, other than nitrogen.”

One key element that isn’t mentioned in the paper is phosphorus, Lingam said. The human body relies on phosphorus to create DNA, RNA and ATP (a vital form of energy storage in cells). All organisms on Earth — including any plants colonists might hope to grow in their floating habitats — need it in one way or another, but Janhunen’s proposal doesn’t address where or how this critical element would be obtained.

The second caveat is the technology, Lingam said. Collecting nitrogen and other raw materials from Ceres would require mining the planet’s surface and extracting those crucial elements from the rocks themselves. This operation likely wouldn’t be possible without a fleet of autonomous mining vehicles ready to deploy on Ceres, plus satellites to guide them to the most viable nutrient-rich deposits. The idea is plausible, Lingam said, but technologically, we aren’t there yet; just recently (on Jan. 15), a NASA Mars robot was declared dead after it failed to bury itself just 16 feet (5 meters) into the Martian surface, terminating a two-year mission.

Those technological limitations point to Lingam’s third caveat, which is the proposed time frame. Janhunen’s proposal suggests that the megasatellite’s first cluster of orbiting habitats could be completed 22 years after mining begins on Ceres. But this estimate assumes the settlement’s available power supply grows exponentially each year, beginning immediately and never stalling due to technological or logistical problems. That estimate “isn’t inconceivable,” Lingam said, but shouldn’t be taken for granted.

“That timescale of 22 years might be the lower bound under optimal conditions, but I’d argue that the real timescale could be a lot longer,” Lingam said.

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Jim Bridenstine has resigned as NASA Administrator.

I don’t really know how the politics work but I know the job is a Presidential appointment, so I’m not sure if he had to resign but presumably Biden will want his own pick there.

When Trump appointed him there was much eye-rolling and despair from (anonymous) NASA insiders because, well, Trump appointed him. But over 4 years, I’ve seen nothing but praise for him. As far as I can see, he ignored politics and just got on with making NASA as good as he could. From my far-outside perspective it seems he did a good job and I hope Biden’s guy is as good.

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A galactic sideswipe 3 billion years ago warped our Milky Way galaxy

New data from the Sloan Digital Sky Survey and Europe’s Gaia spacecraft suggest that a brush with another galaxy caused the strange, potato chip-like “warp” in our Milky Way galaxy.

We know little about our own galaxy’s warp because of the difficulty of studying the galaxy from within it, but scientists have observed similar distortions in roughly 50% to 70% of spiral galaxies like our own. (Technically speaking, the Milky Way is a particular subset of the group, called a barred spiral galaxy.)

The new results suggest that our galaxy’s twist came from a “recent” interaction with another galaxy — recent, that is, compared to the 13.7-billion-year-old age of the universe. Roughly three billion years ago, the scientists suggest, a satellite galaxy came close enough to our own to create a ripple effect still visible in the Milky Way’s stars today.

“Our usual picture of a spiral galaxy is as a flat disk, thinner than a pancake, peacefully rotating around its center,” lead author Xinlun Cheng, an astronomy graduate student at the University of Virginia, said in a statement from Sloan. “But the reality is more complicated.”

It’s difficult for scientists to map out our galaxy’s warp because Earth is embedded deep in the Milky Way. Even our spacecraft have only ventured a little ways from our planet, in cosmic terms, as most remain within the bubble our star forms around the planets.

A view of a spiral galaxy seen nearly edge-on.

Instead, scientists learn about the warp by studying the motions and positions of stars throughout the Milky Way. The new results show that the galactic disk’s warp ripples through the Milky Way once every 440 million years.

“Imagine that you are in the stands at a football game, and the crowd starts doing ‘the wave,'” Cheng said. “All you do is stand up and sit down, but the effect is that the wave goes all the way around the stadium. It’s the same with the galactic warp — stars only move up and down, but the wave travels all the way around the galaxy.”

Scientists gathered the information using the Apache Point Observatory Galactic Evolution Experiment (APOGEE), which has observed hundreds of thousands of the Milky Way’s stars in the past decade. APOGEE gathers a star’s spectrum, or the different light wavelengths emitted, as part of its survey.

Then, astronomers added observations from the European Space Agency’s Gaia satellite, which measures cosmic distances to stars all over the galaxy. Together, the two sets of observations provided a three-dimensional map of Milky Way stars along with their velocities and chemistries.

The study may help astronomers create more accurate models of the forthcoming collision of the Milky Way with the nearby Andromeda Galaxy (M31) in roughly 4.5 billion years, the scientists said.

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Todd

Powerful cosmic eruptions traced to brilliant ‘magnetar’ in nearby galaxy

Astronomers may have captured the first good look at giant flares from the strongest magnets in the universe.

The likely cause of these giant flares? Starquakes trillions of trillions of times stronger than any earthquakes, scientists reported at the 237th American Astronomical Society meeting, held virtually last week.

The most powerful magnets in the cosmos are magnetars, which possess magnetic fields about 100 trillion times more powerful than Earth’s, or 10 trillion times that of an ordinary fridge magnet, Kevin Hurley, an astrophysicist at the University of California, Berkeley, said during a news conference held Jan. 13.

Detections of GRB 200415A by NASA’s Fermi, Wind, Mars Odyssey and Swift missions provide bands of possible locations, and these bands overlap in the central region of the Sculptor galaxy.

Magnetars are a rapidly spinning kind of neutron star, which is a corpse of a star that died in a catastrophic explosion known as a supernova. “Magnetars are up to a thousand times more magnetic than ordinary neutron stars,” Soebur Razzaque, an astroparticle physicist at the University of Johannesburg and the senior author on one of the studies presented, said in a statement.

“In the Milky Way there are tens of thousands of neutron stars,” Razzaque added. “Of those, only 30 are currently known to be magnetars.”

Once magnetars are born, they only stay magnetars for about 10,000 years before their magnetic fields weaken to render them relatively ordinary neutron stars, Eric Burns, an astrophysicist at Louisiana State University and co-author of the new study, said at the press conference. Magnetars are typically seen in star-forming regions, such as starburst galaxies, he noted.

Previous research discovered magnetars regularly explode with X-ray bursts about one-tenth of a second long that each pack up to about the same amount of energy the sun gives off in a year. In three instances over the past 40 years, astronomers have seen magnetars in the Milky Way and nearby galaxies explode with even brighter, more energetic outbursts of X-rays and gamma rays. However, such giant flares were so powerful, they blinded any sensors that glimpsed them, making them difficult to study in any great detail.

Now researchers may have the best look yet at a giant magnetar flare, one good enough to help them deduce its possible origins.

Scientists analyzed the extremely bright gamma-ray burst GRB 200415A, which five space observatories that form the so-called Interplanetary Network detected on April 15, 2020. Gamma-ray bursts are the most powerful kinds of explosions known in the universe, each giving off as much energy in milliseconds to minutes as the sun is expected to emit during its entire 10-billion-year lifetime.

This graphic shows the three nearest magnetar giant flares ever detected. The first one erupted in 1979 in the Large Magellanic Cloud; the others erupted in 1998 and 2004 within our galaxy.

At its peak, this newfound explosion was about 360 trillion times more luminous than the sun. “That is about 100,000 years of solar energy released in only 140 milliseconds,” Hurley said.

The Interplanetary Network triangulated the location of the gamma-ray burst to the center of the nearby Sculptor galaxy, formally known as NGC 253, which is located about 11.4 million light-years from Earth in the Sculptor constellation. Previously detected GRBs came from relatively far away from the Milky Way, but GRB 200415A originated much closer to home, in cosmic terms.

Gamma-ray bursts are typically divided into two groups — long and short — depending on whether they last more or less than two seconds. Short gamma-ray bursts are most likely caused by the mergers of neutron stars, while long gamma ray-bursts are linked with supernovas.

GRB 200415A lasted just 140 milliseconds, about the blink of an eye. “It’s as fast as snapping your fingers,” Oliver Roberts, an astrophysicist at the Universities Space Research Association in Huntsville, Alabama who led another new study on GRB 200415A, said at the news conference.

This speed would ordinarily suggest it was a short gamma-ray burst. However, the pattern of light seen from this outburst was very different from that seen from short gamma-ray bursts that previous research found were caused by colliding neutron stars.

Instead, GRB 200415A’s light pattern was a near copy of those previously seen from giant magnetar flashes. Those began with an intense flash about one-fifth of a second long, followed by a string of pulses lasting about two to 12 seconds.

The cause of this newfound giant magnetar flare was likely a “starquake” — a rupture of the magnetar’s solid crust, Roberts said. This quake was huge — magnitude 27.8 in strength, or about one thousand trillion trillion (10^27, or a 1 with 27 zeroes behind it) times more powerful “than the largest known terrestrial earthquake, which was the magnitude 9.5 [earthquake] in Chile in 1960,” Hurley said.

The researchers suggested this starquake not only released a bright flash of gamma rays, but also heated the magnetar’s crust. As the magnetar whirls around, this super-hot crust looks like a series of bright flashes that dim as the surface cools, Hurley told Space.com.

The scientists added this starquake likely also spit out a blob of plasma traveling about 99% the speed of light, Nicola Omodei, an astrophysicist at Stanford University who participated in the study, said at the press conference.

After four days, this blob encountered the shockwave created when the giant bubble of plasma around the magnetar, known as its magnetosphere, slammed into the interstellar medium of gas and dust between stars at a speed of about 2.2 million mph (3.6 million kph). When the blob collided with this shockwave, it generated another pulse of gamma rays seen 19 seconds after the initial flash. The gamma rays in this second outburst were even more energetic than those seen in the first one, he noted.

All in all, these new findings suggest that maybe a small percent of known short gamma-ray bursts are caused by giant magnetar flares, Burns said.

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‘Symbiotic stars’ caught snacking on each other outside the Milky Way

An artistic impression of the Draco C1 symbiotic binary star system showing material flowing off the red giant star onto its white dwarf companion.

For the first time, stars snacking on their stellar neighbors outside the Milky Way have had their orbits fully mapped. Using the Sloan Digital Sky Survey, astronomers have identified two pairs of stars beyond the galaxy that are consuming their companions. The new discovery can help astronomers understand if distant galactic environments function similarly to or differently from the Milky Way. It can also provide insight into one of the fundamental methods of measuring distance in the night sky.

More than half the stars in the Milky Way come in pairs. While it seems likely that binary stars should make up a significant fraction of other galaxies, scientists have been unable to confirm that because at such large distances ordinary stars are too faint to see.But so-called symbiotic stars, where one companion consumes the other, can be extremely bright, making them easier to observe.

“Measuring the orbits of these symbiotic star systems is an important step towards learning whether other galaxies create binary stars like those in the Milky Way,” Jasmin Washington, a co-author of the new study and a graduate student at the University of Arizona, said in a statement. She was an undergraduate at the University of Virginia during the project. Washington and her fellow author, Hannah Lewis, a graduate student at the University of Virginia, presented the results on Tuesday (Jan 12) at the 237th meeting of the American Astronomical Society, held virtually last week.

“We have developed for the first time ever the complete understanding of the architecture of an extragalactic [symbiotic] system,” Washington said at the briefing.

Serendipitous snackers

Although a pair of stars may be born together, they can age differently due to their masses. The more massive of the two will quickly burn through its material to reach the end of its lifetime first. If that star is large enough, it will leave behind a compact white dwarf. Although small and dim, white dwarfs can pack the mass of the sun into an object the size of the Earth. If close enough, the gravity of the dense objects can pull material from their companion, creating a signal that astronomers can identify from extremely far away.

While astronomers know that stellar pairs are common in the Milky Way, they remain uncertain how large a fraction they make up in other galaxies.

“The properties of binary systems likely depend on the environment that they formed in,” Lewis said at the briefing. “Those environmental properties can vary vastly between galaxies.”

For the last decade, Sloan Telescope’s Apache Point Observatory Galactic Evolution Explorer (APOGEE) survey has studied the sky, gathering data about hundreds of thousands of stars in the Milky Way and its nearest galactic neighbors. These include the Draco dwarf spheroidal galaxy and the Small Magellanic Cloud (SMC), roughly 260,000 and 200,000 light-years respectively.

“These two galaxies alone show how conditions can vary wildly between systems,” Lewis said. Draco is an ancient galaxy, a hundred thousand times smaller than the Milky Way, and is dominated by dark matter rather than stars. The SMC is younger and larger, only 200 times smaller than our galaxy and composed of old and young stars. Both galaxies are home to a symbiotic stellar pair visible to APOGEE, the Draco C1 and LIN 358 pair, respectively.

This graph shows the motions measured by the APOGEE data for the Draco C1 symbiotic binary star system, which has been monitored repeatedly over the last five years. Black dots represent the data, while the blue curve shows the computer model for the orbit of the red giant as it circles the white dwarf, moving toward and away from the observer.

Slurping material from the neighboring stars only allows astronomers to identify the pair. The Doppler shift — the same phenomena responsible for causing train whistles to reach a higher pitch as they move closer and lower as they move farther away — also causes changes in the frequency of light coming from a star, depending on whether it is moving closer to or farther from the observer. That back-and-forth motion can help astronomers to calculate the full orbit of the binary system and the masses of both stars.

By combing through several years of APOGEE data, Washington realized that the stars in Draco C1 take roughly three Earth years to orbit one another, while LIN 358’s components take just over two. The results reveal the first full orbital measurements of any symbiotic star system outside the Milky Way.

“Very few symbiotic stars have ever been monitored long enough for astronomers to watch the full willing dance,” Lewis said in a statement. “And no one has ever done this in detail for symbiotic stars in other galaxies.”

The new measurements will help astronomers better understand star formation in other galaxies.

“Dwarf galaxies have very different internal environments and evolutionary histories from the Milky Way,” Borja Anguiano, also at the University of Virginia, said in the statement. A co-author on the paper, Anguiano originally discovered that APOGEE had serendipitously observed Draco C1 and LIN 358 several times.

“Soon we will have enough orbits mapped for binaries in other galaxies that we may begin to answer the question of whether different types of galaxies are more efficient at making binary stars.”

The results from the observations of Draco C1 were published earlier this year in the Astrophysical Journal Letters.

Standard candles

In some symbiotic stars, the white dwarf can slurp enough material from its companion that it explodes in a Type Ia supernova. These extremely bright blasts can be seen across the universe, and they all start out with the same brightness for a nearby observer. Astronomers can use the apparent brightness of the supernova to calculate its distance, making Type Ia supernovas a “standard candle” for measuring the universe.

While Draco C1 and LIN 358 are unlikely to explode as supernovae anytime soon, understanding how they work can provide insights into how these standard candles evolve.

“Because we rely on Type Ia supernovae as distance measurements, it’s important that we understand exactly how they work, and what systems we should be looking for as possible supernovae progenitors,” Anguiano said. “Being able to study the orbits of symbiotic stars in other galaxies will allow us to confirm whether the process of forming Type Ia supernovae is universal.”

Mapping the orbital characteristics of Draco C1 and LIN 358 is a “first incredible step” towards using a decade’s worth of APOGEE data to understand binary stars outside the Milky Way, Washington said at the briefing.

“Studying extragalactic symbiotic stars in great detail and being able to precisely derive their orbits and stellar parameters could provide important insights into these cosmic markers,” she said.

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Mystery particle may explain extreme X-rays shooting from the ‘Magnificent 7’ stars

Never-before-seen particles called axions could be behind the mysterious X-rays.

An artistic rendering of the XMM-Newton (X-ray multi-mirror mission) space telescope. A study of archival data from the XMM-Newton and the Chandra X-ray space telescopes found evidence of high levels of X-ray emission from the nearby Magnificent Seven neutron stars, which may arise from the hypothetical particles known as axions.

More than 400 light-years from Earth, there is a cluster of young neutron stars that are too hot for their age. These stars, known as the “Magnificent Seven,” emit a stream of ultra-high-energy X-rays that scientists haven’t been able to explain.

Now, scientists have proposed a possible culprit: axions, theoretical particles that turn into light particles when they are in the presence of a magnetic field.

In a new study, published Jan. 12 in the journal Physical Review Letters, Lawrence Berkeley National Laboratory physicist Benjamin Safdi and colleagues used supercomputers to model the idea that axions produced inside the stars could convert to X-rays in the magnetic fields outside the stars. Axions have never been observed directly, but they were first theorized to exist in the 1970s. It’s too soon to say for sure whether axions exist or whether they’re the true culprit for the weird X-rays, Safdi said, but researchers hope the new computer modeling may point to something outside the Standard Model of physics, which describes known subatomic particles.

“We are pretty confident this [X-ray] excess exists and very confident there’s something new among this excess,” Safdi said in a statement. “If we were 100% sure that what we are seeing is a new particle, that would be huge. That would be revolutionary in physics.”

Mysterious X-rays

Given their age and type, the Magnificent Seven should be emitting only low-energy X-rays and ultraviolet light. But astronomers have observed something they can’t explain: high-energy X-rays coming off the stars. Neutron stars are the leftovers from giant stars that have exhausted their fuel and collapsed; one type of neutron star, called a pulsar, gives off emissions across the electromagnetic spectrum, including high-energy X-rays. But the Magnificent Seven aren’t pulsars.

Scientists have also searched behind the neutron star cluster for other objects that could be emitting the mysterious X-rays, but neither the European Space Agency’s XMM-Newton telescope nor NASA’s Chandra X-ray telescope has turned up anything that could be the culprit.

Axions have also been proposed as a solution to the mystery. But could axions really be produced inside a neutron star? To find out, Safdi and his colleagues turned to supercomputers at the University of Michigan and Lawrence Berkeley National Laboratory.

“There is a lot of data processing and data analysis that went into this,” Safdi said. “You have to model the interior of a neutron star in order to predict how many axions should be produced inside of that star.”

Elusive axions

An axion, if it exists, is an elementary particle with a very low mass. Axions might be a component of dark matter, the unobserved stuff that seems to make up over a quarter of the universe’s mass, based on its gravitational effects.

Safdi and his team found that axions might work a lot like neutrinos, another extremely light subatomic particle that has been shown to exist. Neutrinos are produced inside neutron stars when neutrons bump into one another; axions could be produced in the same way.

Given their low mass and weak interactions with other matter, axions could easily escape the cores of neutron stars and zip out into space. Extremely strong magnetic fields surround neutron stars. In the presence of these fields, axions would convert into photons, or light particles. Traveling at wavelengths shorter than visible light, these light particles would register as high-energy X-rays on astronomical instrumentation.

“We’re not claiming that we’ve made the discovery of the axion yet, but we’re saying that the extra X-ray photons can be explained by axions,” Raymond Co, a postdoctoral researcher at the University of Minnesota who collaborated on the study, said in the statement. “It is an exciting discovery of the excess in the X-ray photons, and it’s an exciting possibility that’s already consistent with our interpretation of axions.”

The next step, Safdi said, is to look for axions in white dwarfs, another set of stars that shouldn’t emit X-rays.

“This starts to be pretty compelling that this is something beyond the Standard Model if we see an X-ray excess there, too,” he said.

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Scientists spot 6 alien worlds orbiting a star in strange — but precise — harmony

The planets around the star TOI-178 know how to keep a beat.

The planets around a star called TOI-178 know how to keep a beat — so smoothly, in fact, that scientists were able to discover new alien worlds by deciphering the system’s music.

Astronomers poring through data from NASA’s Transiting Exoplanet Survey Satellite (TESS) discovered three planets around a star dubbed TOI-178 (TOI stands for TESS Object of Interest). And when scientists looked at these observations more closely, they realized that the worlds seemed to be keeping time against each other. So they recruited some more instruments — and discovered the system hosts at least six planets, five of which tick off orbits in rhythm with the others. And unlike those of other synchronized systems, the planets are an unusually mixed bag.

“It is the first time we observe something like this,” Kate Isaak, project scientist for the European Space Agency’s Characterizing Exoplanet Satellite (CHEOPS), one of those additional instruments, said in a statement released by the University of Bern in Switzerland. “In the few systems we know with such a harmony, the density of planets steadily decreases as we move away from the star. In the TOI-178 system, a dense, terrestrial planet like Earth appears to be right next to a very fluffy planet with half the density of Neptune, followed by one very similar to Neptune.”

An artist’s depiction of the TOI-178 system.

Inspired by the mysterious TESS data showing three planets in an odd rhythm, the scientists behind the new research recruited additional instruments culminating in a dozen days of observing time with the CHEOPS telescope.

From those observations, the TOI-178 system appeared to include five planets, which orbited the star every 2, 3, 6, 10 and 20 days. But to the scientists, there appeared to be a gap in that sequence: They thought there should be another planet in the system, this one orbiting every 15 days.

Back to CHEOPS the researchers went, although they nearly missed their chance at studying the system in detail. Just as CHEOPS was due to take crucial observations of TOI-178, the satellite had to hustle away from a potential collision with a piece of space junk.

Despite the close call, all went smoothly in the end.

“To our great relief, this maneuver was done very efficiently and the satellite could resume observations just in time to capture the mysterious planet passing by,” Nathan Hara, an astrophysicist at the University of Geneva and co-author on the new research, said in the statement. “A few days later, the data clearly indicated the presence of the additional planet and thus confirmed that there were indeed six planets in the TOI-178 system.”

The innermost of those, it turns out, marches to a different beat, but the outer five orbit in harmony with each other. For every complete orbit of the outermost world, the next in completes three-quarters of an orbit, the middle world in the sequence makes two loops, then a planet that makes three orbits, and then a planet that makes six orbits; along the way, the planets occasionally line up, which caused the strange rhythm in the original TESS data.

Not only could the researchers spot the additional planets and sort out the complicated chain of orbits, but the scientists could also study the planets themselves, finding that these worlds range from 1.1 to 3 times the size of Earth, but with a range of densities, making them a curious mix of rocky super-Earths and gassy mini-Neptunes.

The scientists suspect that there may be more planets following the same chain of orbital alignments, although spotting these worlds would require longer periods of observation. Fortunately, because the star itself is so bright, the system is relatively easy to study; in particular, the researchers look forward to the data that NASA’s James Webb Space Telescope and the European Extremely Large Telescope might be able to gather about the system once each begin work.

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‘Sextuply-eclipsing sextuple star system’ discovered whirling through the Milky Way

If you’ve ever ridden a teacup ride at a state fair you might be ready for life in the six-star system TIC 168789840.

An illustration shows the Transiting Exoplanet Survey Satellite (TESS). Data from TESS has revealed a sextuple star system less than 2,000 light years from Earth.

Ever ridden a teacup ride at a state fair? If so, you might have a small taste of life in a whirling, twirling sextuply-eclipsing sextuple star system.

“Sextuply-eclipsing sextuple star system” is astronomer-speak for a system with six stars all orbiting each other and all regularly eclipsing one another from the perspective of Earth — and astronomers have just found one named TIC 168789840.

This six- star system is far enough from Earth (a bit less than 2,000 light-years away) that telescopes can’t resolve its individual stars, which blur together into a single point of light. Instead, astronomers were able to spot that point of light brightening and dimming in an unusual pattern, thanks to the stars’ penchant for regularly eclipsing one another.

These eclipses are visible due to a spot of luck: TIC 168789840’s stars orbit on a plane that lines up perfectly with Earth, so every time one of the stars passes another, it creates an eclipse that is visible to Earth’s telescopes. From a different vantage point, the stars would never block each other, and the system would just be another point of light in space.

This isn’t the first sextuple system ever discovered, the astronomers noted in a paper published Jan. 12 to the arXiv database (it has not yet been peer-reviewed) But the star system joins a club with just three other members, including Castor, a famous system discovered in 1920.

Castor, known since ancient times as one of the stars in the constellation Gemini, was identified as a binary system in 1719 by the English clergyman and astronomer James Pound. Just 51 light-years from Earth, the system revealed itself to Pound through a telescope as two points of light dancing around each other. By 1905, astronomers realized those two points were actually both pairs of stars tightly orbiting each other and circling a common center; and by 1920, another team spotted a third pair of stars circling the inner four, making it a six-star system.

A NASA illustration shows the complex sextuple orbits of the nearby star system Castor. The newly-discovered system has a similar arrangement of stars.

There are other ways for six-star systems to organize themselves. ADS 9731, for example, comprises four points of light circling a common center. Two of those points of light are tight binaries, making it a sextuple system.

But “TIC 168789840 is most similar to the famous Castor system,” the authors wrote.

There are two inner pairs of stars each whipping around in tight circles. (The first pair completes a binary orbit every 31 hours, the second every 38 hours.) And those binaries — the “inner quadruple” — complete a circuit around a common center about once every 3.7 years.

Compared with the inner couples, the outer binary’s two stars are less cozy with each other, turning a binary orbit only once every 197 hours. And the binary pair only completes its circuit of the whole system once every 2,000 years or so.

Identifying distant, dim TIC 168789840 was a higher-tech enterprise than James Pound’s telescope observations of close, bright Castor. The researchers used the NASA supercomputer Discover to dig through years of data from the Transiting Exoplanet Survey Satellite (TESS), which is tuned to look for changes in the light of stars all over the sky.

The researchers trained a “neural network” — a type of artificial intelligence — running on Discover to look for patterns of dimming and brightening that could indicate complex systems. But most of what turned up were boring binaries. Careful study of TIC 168789840, however, revealed something unusual going on, and follow-up observations confirmed the presence of six stars.

Researchers still don’t know precisely how complex multiple-star systems form, the authors wrote in the paper. This discovery offers critical data for untangling that problem. And more data could soon be on the way.

“TESS has allowed us to find well over 100 such candidate multi-star systems to date, with the analysis of another sextuple system … to follow this in the near future,” they wrote.

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NASA finds ‘Lost Galaxy’ shining out of Virgo’s bosom

This hazy spiral galaxy is one of the largest in the Virgo cluster — a collection of more than 2,000 galaxies.

The spiral galaxy NGC 4535 is better known as the ‘Lost Galaxy’ for its famously hazy appearance.

In the 1950s, when amateur astronomer Leland S. Copeland first fixed his telescope lens on a distant galaxy in the Virgo constellation, he saw an eerie spiral shrouded in dust. Copeland — who was a professional poet fond of writing about the cosmos — dubbed the spiral “The Lost Galaxy,” a name that has stuck some 70 years later.

Less-poetic scientists know this galaxy as NGC 4535, one of the largest of the 2,000-or-so galaxies in the Virgo Cluster located about 50 million light-years from Earth. When viewed through NASA’s Hubble Space Telescope, which captured the stunning image above, the haze that clouded Copeland’s Lost Galaxy vanishes to reveal a vibrant sea of stars not so different from the Milky Way.

Like our home galaxy, The Lost Galaxy is a barred spiral galaxy: a vast swirl of stars with a distinct bar structure at its center. According to NASA, the colors of those stars can tell us a bit about the galaxy’s history.

The yellowish glow of the galaxy’s central bulge points the way to The Lost Galaxy’s oldest, coldest retinue of stars, NASA representatives wrote in a statement; meanwhile, bright blue clouds clustered together in the galaxy’s spiral arms reveal where its hottest, youngest stars congregate, lighting up the gas and dust around them.

Today, The Lost Galaxy is not hard to find (especially for floating observatories like Hubble). In fact, its long, elegant arms make it a prime candidate for studying the structure of spiral galaxies. NASA released the image above on Jan. 11 as part of an ongoing survey of 38 spiral galaxies located within 75 million light-years of Earth. You can see some equally stunning images of other nearby spiral galaxies from the survey — known as the Physics at High Angular resolution in Nearby GalaxieS (PHANGS) survey — on the project’s website.

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Mysterious ‘kick’ just after the Big Bang may have created dark matter

New research suggests a mysterious “kick” in the early universe may have lead to the creation of dark matter.

One of the lingering mysteries of the universe is why anything exists at all.

That’s because, in the universe today, matter and its antimatter counterpart should form in equal amounts, and then these two oppositely charged types of matter would annihilate each other on contact. So all the matter in the universe should have disappeared as soon as it formed, canceling itself out on contact with its antimatter counterpart.

But that didn’t happen. Now, new research hypothesizes that early in the universe, there was a mysterious “kick” that produced more matter than antimatter, leading to today’s imbalance. And that imbalance may have also led to the creation of dark matter, the mysterious substance that tugs on everything else yet doesn’t interact with light.

Coincidence or conspiracy?

We don’t know what dark matter is, but it’s definitely out there. It makes up about 80% of all the matter in the universe, far outweighing the stars, galaxies, dust and gas that we can see.

And while dark matter is certainly a heavyweight in our universe, it is, oddly, not that much of a dominating factor. Typically, in physics, when one process dominates an interaction, it really takes over. Unless other physics comes into play, rarely do two competing forces come out in balance. For example, when the forces of gravity and electromagnetism compete inside a giant star, eventually gravity always wins and the star collapses. So the fact that dark matter is 80% of the mass in the universe — and not 99.99999% — and regular matter is 20% as opposed to zero, strikes physicists as odd. An 80/20 split doesn’t seem even when it comes to, say, sharing lotto winnings, but to an astronomer, the two amounts are practically the same.

Compounding the issue is that, as far as we know, the generation of regular matter and dark matter had absolutely nothing to do with each other. We have no clue how dark matter originated in the early universe, but whatever it was, it’s currently outside the bounds of known physics.

And regular matter? That’s a whole other kettle of particles. In the extremely early universe (when it was a second old), physicists suspect that regular matter was in perfect balance with antimatter (which is the same as normal matter but with an opposite electric charge). We suspect this even split because we see this kind of symmetry play out today in our particle colliders, which can replicate the extreme conditions of the early universe: If you have a high-energy reaction that generates regular matter, it has an equal chance of generating antimatter instead.

But at some point (we’re not exactly sure when, but it most likely happened when the universe was less than a minute old), the balance between matter and antimatter shifted, and regular matter flooded the universe, relegating antimatter to obscurity.

So, on one hand, we have a massive symmetry-breaking event that led to regular matter winning over antimatter. On the other hand, we have a completely mysterious event that led to dark matter becoming the dominant — but not super dominant — form of matter in the universe.Perhaps these two processes are connected, and the birth of dark matter was related to the victory of matter over antimatter, the new study proposes.

Mining for goldstone

In the study, published online Dec. 29, 2020, in the preprint database arXiv and not yet peer-reviewed, researchers make this claim by relying on something called the baryon number symmetry. Baryons are all of the particles made of quarks (such as protons and neutrons). The symmetry simply states that the number of baryons entering an interaction must equal the number exiting it. (They’re allowed to change identities, but the total number must be the same.) The same symmetry holds for reactions involving antiquarks.

This symmetry reigns in all of our experiments in the present-day universe, but it must have been violated in the early cosmos — that’s how we ended up with more matter than antimatter.

And in physics, every time a symmetry of nature gets broken, a new kind of particle, known as a “Goldstone boson,” pops up to enforce the breaking of the symmetry. (In the modern universe, for instance, the pion is a kind of Goldstone boson that appears when a symmetry of the strong nuclear force is broken.)

Maybe the dark matter is a kind of Goldstone boson, associated with the breaking of baryon number symmetry in the early cosmos, the study proposes.

Kicking the can

The researchers behind the idea call it “the kick.” Baryon number symmetry is never broken in our experiments, but something exciting must have happened in the early universe. It was a violent but brief event, snuffing out almost all antimatter. And whatever exotic mix of conditions happened, the baryon number symmetry broke, allowing a new Goldstone boson to appear.

So, the thinking goes, during that singular event, the universe became flooded with dark matter particles. But then, whatever conditions that led to the symmetry breaking ended, and the universe returned to normalcy. By then, however, it was too late; the dark matter — and all the rest of the matter — remained.

So after that first epic minute of the universe’s history, once symmetry returned to the universe, dark matter was relegated to the shadows, never to interact with normal matter again.

And the reason that there is (very roughly) the same amount of dark matter and regular matter is that they were related, the study claims. The new model doesn’t predict the exact 80/20 split between dark and normal matter. But it does suggest the reason that dark matter and normal matter are in roughly equal balance is because they had their origins in the same event.

It’s a very clean and intriguing idea, but it still doesn’t explain exactly how that early symmetry breaking took place. But that’s for another paper.

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bosoms(bosons?) and sex(tuple). You are really trying to spice thing up here, Sean

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We may have found the most powerful particle accelerator in the galaxy

And it’s quite a surprising source.

This image, created using data from the European Space Agency’s Herschel and Planck space telescopes, shows a piece of the Taurus Molecular Cloud.

Astronomers have long wondered where high-energy cosmic rays come from within our galaxy.

And now, new observations with the High Altitude Water Cherenkov Experiment (HAWC) observatory reveal an unlikely candidate: an otherwise mundane giant molecular cloud.

Taking the knee

Cosmic rays are not rays at all but rather tiny particles cruising through the universe at nearly the speed of light. They can be made of electrons, protons or even ions of heavier elements. They are created in all sorts of high-energy processes throughout the cosmos, from supernova explosions to the mergers of stars to the final insane moments when gas gets sucked up by a black hole.

Cosmic rays come in all sorts of energies, and generally speaking the higher-energy cosmic rays are rarer than their low-energy relatives. This relationship changes in a very slight way at a particular energy — 10^15 electron-volts — which is called the “knee.” The electron-volt, or eV, is just the way that particle physicists enjoy measuring energy levels. For comparison, the most powerful particle collider on Earth, the Large Hadron Collider, can achieve 13 X 10^12 eV, which is often denoted as 13 tera electron-volts, or 13 TeV.

Above an energy of 10^15 eV, cosmic rays are much rarer than you would expect. This has led astronomers to believe that any cosmic rays at this energy level and higher come from outside the galaxy, while processes within the Milky Way are capable of producing cosmic rays up to and including 10^15 eV.

For those of you keeping score at home, whatever is creating these cosmic rays would be in the “peta” range of Greek prefixes, and therefore over 1,000 times more powerful than our best particle accelerators — natural “PeVatrons” roaming the galaxy.

A hawkeyed sleuth

The mission is simple: find the source of PeV-scale cosmic rays in the Milky Way. But despite their energies, it’s hard to pinpoint their origins. That’s because cosmic rays are made of charged particles, and charged particles traveling through interstellar space respond to our galaxy’s magnetic field. Thus when you see a high-energy cosmic ray coming from a particular direction in the sky, you actually have no idea where it truly came from — its path has bent and curved over the course of its journey to Earth.

But instead of hunting for cosmic rays directly, we can search for some of their relatives. When cosmic rays accidentally strike a cloud of interstellar gas, they can emit gamma rays, a high-energy form of radiation. These gamma rays shoot straight-line through the galaxy, allowing us to directly pinpoint their origins.

So if we see a source of strong gamma-ray emission, we can look for nearby sources of PeV cosmic rays.

This was the method employed by a team of researchers using HAWC, which is located on the Sierra Negra Volcano of south-central Mexico. HAWC “stares” up at the sky with a series of tanks filled with ultra-pure water. When high-energy particles or radiation enter the tanks, they emit a flash of blue light, allowing astronomers to trace back the source onto the sky.

Detailed in a paper recently appearing in the preprint journal arXiv, the astronomers found a source of gamma rays exceeding 200 TeV, which could only be created by even more powerful cosmic rays — the kinds of cosmic rays that reach up into the PeV scale. The source, called HAWC J1825-134, lies roughly in the direction of the galactic center. HAWC J1825-134 appears to us as a bright blotch of gamma rays, illuminated by some unknown fount of cosmic rays — perhaps the most powerful known source of cosmic rays in the Milky Way.

An unlikely heavyweight

A few of the usual suspect sources of high-energy cosmic rays sit within a few thousand light-years of HAWC J1825-134, but none of them can easily explain the signal.

For example, the galactic center itself is a known generator of intense cosmic ray action, but it’s way too far away from HAWC J1825-134, so it has no bearing on this measurement.

There are some supernova remnants, and supernovae sure are powerful. But all the supernovae in the region of HAWC J1825-134 went off ages ago — far too long in the past to be creating these high-energy cosmic rays now.

Pulsars — the rapidly spinning dense remnant cores of massive stars — also produce copious amounts of cosmic rays. But those too sit too far away from the source of gamma rays — the energies of the electrons and protons coming off the pulsar just aren’t punchy enough to travel the thousands of light-years to the location of the gamma ray emission.

Surprisingly, the source of these record-breaking cosmic rays appears to be none other than a giant molecular cloud. These clouds are giant, lumbering brutes, filled with dust and gas, that roam the galaxy. They occasionally contract in on themselves and turn into stars, but otherwise they can remain cool and loose for billions of years. Not causing anyone any serious threat — and barely even noticeable unless you have good infrared telescopes — they are the last place you would expect to find such insanely high energies.

Located within the cloud complex is a cluster of newborn stars, but even the crankiest and loudest of baby stars aren’t thought to be powerful enough to launch cosmic rays like this. The researchers themselves admit that they don’t know how this cloud is doing it, but somehow, when nobody was paying attention, it generated some of the most powerful particles in the entire galaxy.

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Earth’s outer shell ballooned during massive growth spurt 3 billion years ago

Ancient fragments of Earth’s crust acted as ‘seeds’ for new crust to grow from.

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Scientists solve a major climate mystery, confirming Earth is hotter than it’s been in at least 120 centuries

Scientists have resolved a controversial but key climate change mystery, bolstering climate models and confirming that Earth is hotter than it’s been in at least 12,000 years, and perhaps even the last 128,000 years, according to the most recent annual global temperature data.

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Doomsday Clock stands at 100 seconds to midnight

Our destruction is close, but it creeps no closer … for now.

During Operation Upshot-Knothole, the U.S. Army exploded 11 nuclear bombs at a test site in Nevada between March and June in 1953. In the last of those tests — code name “Climax” — a 61-kiloton device was detonated on June 4, 1953.

Clickest…

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Earth is about to lose its second moon, forever

Godspeed, SO 2020. Enjoy your journey around the sun.

Earth’s second moon will make a close approach to the planet next week before drifting off into space, never to be seen again.

“What second moon,” you ask? Astronomers call it 2020 SO — a small object that dropped into Earth’s orbit about halfway between our planet and the moon in September 2020. Temporary satellites like these are known as minimoons, though calling it a moon is a bit deceptive in this case; in December 2020, NASA researchers learned that the object isn’t a space rock at all, but rather the remains of a 1960s rocket booster involved in the American Surveyor moon missions.

This non-moon minimoon made its closest approach to Earth on Dec. 1 (the day before NASA identified it as the long-lost booster), but it’s coming back for one more victory lap, according to EarthSky.org. Minimoon 2020 SO will make a final close approach to Earth on Tuesday (Feb. 2) at roughly 140,000 miles (220,000 kilometers) from Earth, or 58% of the way between Earth and the moon.

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‘Elves’ and ‘blue jet’ lightning in Earth’s stratosphere spotted from space

The space station detected several “elves” and a “blue jet” in a thunderstorm over the Pacific Ocean.

Newly published observations from space are showing researchers more about the nature of Earth’s lightning storms, including whimsically named phenomena such as “blue jets” and “elves.”

The International Space Station’s Atmosphere-Space Interactions Monitor (ASIM) observatory caught a single blue “jet” (upward-shooting lightning) from a thunderstorm cell, along with four “elves,” or optical and ultraviolet emissions from the bottom of the ionosphere, according to a Nature paper published Wednesday (Jan. 20).

ASIM, a European instrument, can peer down at lightning from space. Its unique perch allows researchers to chase down elusive lightning phenomena that remain poorly understood after decades of research, mostly from ground observations.

Artist impression of lightning in clouds seen from space followed by a blue flash that lasts 10 micro seconds, a blue jet lasting 400 milliseconds and an elve generated by the blue flash that lasts for 30 microseconds. The International Space Station’s solar panels are shown in the foreground.

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The 7 alien planets orbiting TRAPPIST-1 are like peas in a pod

The densities of the seven exoplanets vary by no more than 3%.

The seven rocky planets orbiting the red dwarf star TRAPPIST-1 have remarkably similar densities, suggesting they likely have similar compositions, too.

Located about 40 light-years from Earth, TRAPPIST-1 hosts seven rocky planets that are about the size of Earth or smaller — the largest group of roughly Earth-size planets ever found in a single stellar system.

Earlier studies measured the mass and diameter of the TRAPPIST-1 planets, and found they are rocky, or terrestrial, like Earth. However, a new study measured the density of the rocky worlds in greater precision, suggesting that all of the planets are about 8% less dense than Earth, according to a statement from NASA’s Jet Propulsion Laboratory.

More in link…

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Neutrons’ ‘evil twins’ may be crushing stars into black holes

The universe may be filled with “mirror” particles — and these otherwise-undetectable particles could be shrinking the densest stars in the universe, turning them into black holes, a new study suggests.

These hypothetical evil twins of ordinary particles would experience a flipped version of the laws of physics, as if the rules that govern known particles were reflected in a looking glass. According to a new study, published in December 2020 in the preprint database arXiv but not yet peer-reviewed, if these particles exist, they would be shrinking the densest stars in the universe into black holes.

More in link…

Neutron stars are essentially city-size atomic nuclei composed of individual neutrons crammed together just about as tightly as possible. Shown here, an illustration of a neutron star whose gravity is distorting its neighbor, a white dwarf star.

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‘Spooky action at a distance’ could create a nearly perfect clock

Physicists imagine a day when they will be able to design a clock that’s so precise, it can detect dark matter.

Physicists imagine a day when they will be able to design a clock that’s so precise, it will be used to detect subtle disturbances in space-time or to find the elusive dark matter that tugs on everything yet emits no light. The ticking of this clock will be almost perfect.

That dream may not be far off: A group of researchers has created a clock that, with some tweaks, could be four to five times more precise than the world’s best clocks. To put that into perspective, if today’s most precise clocks started ticking at the birth of the universe, they would be off by only half a second today; with more improvements, this new clock has the potential to be off by only 0.1 second.

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Twisted light from the beginning of time could reveal brand-new physics

In this all-sky map from Planck, a European Space Agency mission, the towers of fiery colors represent dust in the galaxy and beyond that has been polarized.

A twist in the universe’s first light could hint that scientists need to rethink physics.

A pair of Japanese scientists looked at the polarization or orientation of light from the cosmic microwave background radiation, some of the earliest light emitted after the universe’s birth. They found the polarization of photons, or light particles, might be slightly rotated from their original orientation when the light was first produced. And dark energy or dark matter may have been responsible for that rotation. (Dark energy is a hypothetical force that is flinging the universe apart, while proposed dark matter is a substance that exerts gravitational pull yet does not interact with light.)

The rotated signature of the photon polarization tells the scientists that something may have interacted with those photons — specifically something that violates a symmetry physicists call parity. This symmetry or parity says that everything looks and behaves the same way, even in a flipped system — similar to how things look in the mirror. And if the system was following this parity rule, there wouldn’t be this rotation change.

Parity is shown by all subatomic particles and all forces except the weak force. However, the new results suggest that whatever the early light might have interacted with might be violating this parity.

“Maybe there is some unknown particle, which contributes to dark energy, that perhaps rotates the photon polarization,” said study lead author Yuto Minami, a physicist at the Institute of Particle and Nuclear Studies (IPNS) of High Energy Accelerator Research Organization (KEK) in Japan.

When the cosmic microwave background radiation, or CMB, was first emitted 13.8 billion years ago, it was polarized in the same direction. Looking at how the light’s polarization has rotated over time allows scientists to probe the universe’s history since then, by looking at how the light has changed as it travels across space and time.

Previously, scientists have studied the CMB’s polarization and how it’s been rotated over time, but they weren’t able to measure it accurately enough to study parity because of large uncertainty in the calibration of the detectors that measure the photon’s polarization. In the new study, reported Nov. 23 in the journal Physical Review Letters, researchers figured out a way to precisely measure the rotation of the instruments by using another source of polarized light — dust from within the Milky Way. Because this light hasn’t traveled as far, it’s likely not strongly affected by dark energy or dark matter.

Using the dusty Milky Way light, the scientists were able to figure out precisely how their instruments were oriented, so they knew the rotation in the light was real, not something caused by their instruments. This allowed them to determine the polarization rotation of CMB light was non-zero, which means that the light has interacted with something that violates parity. It’s possible something in the early universe affected the light, but it’s more likely that it was something along the light’s path as it traveled toward Earth, Minami told Live Science.

That something could be dark energy or dark matter, which would mean that the particles that make up these mysterious substances violate parity.

The authors reported their findings with 99.2% confidence, meaning there’s an 8 in 1,000 chance of getting similar results by chance. However, this isn’t quite as confident as physicists require for absolute proof. For that, they need five sigma, or 99.99995% confidence, which likely isn’t possible with data from just one experiment. But future and existing experiments might be able to gather more accurate data, which could be calibrated with the new technique to reach a high-enough level of confidence.

“Our results do not mean a new discovery,” Minami said. “Only that we found a hint of it.”

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Space calendar 2021: Rocket launches, sky events, missions & more!

Feb. 11: The new moon arrives at 2:06 p.m. EST (1906 GMT)

Feb. 27: The full moon of February, known as the Full Snow Moon, arrives at 3:17 a.m. EST (0817 GMT)

March 13: The new moon arrives at 5:21 a.m. EST (1021 GMT)

March 20: Vernal Equinox. Today marks the first day of spring in the Northern Hemisphere and the first day of autumn in the Southern Hemisphere.

March 28: The full moon of March, known as the Full Worm Moon, arrives at 2:48 p.m. EDT (1817 GMT)

Tons more. Rockets of all kinds from multiple countries (as it says in the link).

But if I only quoted the moons I could’ve just used this link – 2021 Full Moon Calendar

There’s also this – Best night sky events of February 2021 (stargazing maps)

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Aliens could be sucking energy from black holes. That may be how we’ll find them.

Aliens could be sucking power from black holes — and that could be how we’d spot the extraterrestrials, scientists say.

This energy-harvesting technology could leave traces just outside a spinning black hole’s event horizon — the boundary beyond which a black hole’s gravity becomes too strong for matter and energy to escape. And the process could explain at least some flares of plasma, a white-hot form of charged gas, that scientists have already detected near these massive disruptions in time and space. a new study published Jan. 13 in the journal Physical Review D proposes.

And while it’s only a science-fiction idea at the moment — the nearest black hole to us is thought to be more than 1,000 light-years away, which is too far to be reached in many human lifetimes — if astrophysicists could ever work out a method of tapping these cosmic behemoths, rotating black holes could become a near-limitless source of energy for a technologically advanced civilization.

The co-author of the study, astrophysicist Luca Comisso of Columbia University in New York, said the next step will be to figure out what deliberate extraction energy from a black hole might look like to distant observers.

Doing so would allow Earthlings to potentially detect distant alien civilizations, Comisso told Live Science.

“We have only done the physics in this paper,” he said. “But I am now working with a colleague of mine to apply this to reality, to look for civilizations, to try to see what kind of signal you would need to look for.”

Spinning black holes

This is the fourth time in 50 years that a new way to suck energy from a spinning black hole has been proposed. The most famous is a 1969 study by the renowned physicist Roger Penrose, who won the Nobel Prize in physics in 2020 for his work on black holes.

He proposed a mechanism known as the Penrose process, in which a particle breaks in two just beside a black hole rotating at near the speed of light. Part of the particle then falls through the ergosphere, a chaotic region of space-time just outside the black hole’s event horizon, before falling into the black hole itself.

“Because the black hole rotates so fast, it drags space-time around like a vortex,” Comisso said.

According to the calculations, objects falling into this ergosphere can have negative energy, which is not possible anywhere else in the universe. “This is the only tiny region where this can happen,” Comisso said.

And because adding a particle with negative energy to a black hole is equivalent to extracting energy from it, aliens could effectively tap the black hole’s energy by capturing the part of the particle that has escaped the black hole’s intense gravity, he said. “It’s like feeding the black hole with negative energy.”

While in his original study, Penrose considered only a single particle that splits in two, the latest research considers astronomically sized plasmas generated in the accretion disk around a black hole — the often massive and super-hot disk of doomed matter that orbits most black holes. Because plasmas have huge number of particles, they could yield correspondingly huge amounts of energy.

In theory, black holes also “evaporate” over time by giving off Hawking radiation — a quantum mechanical concept proposed by the physicist Stephen Hawking — but that process is too faint to have yet been detected, Comisso said.

Magnetic reconnections

Comisso and co-author Felipe Asenjo, an astrophysicist at the Universidad Adolfo Ibáñez in Santiago, Chile, suggest the plasmas for extracting energy from a spinning black hole are created by “magnetic reconnection” events — where intense magnetic field lines tangle, break and rejoin — just outside its event horizon.

Magnetic reconnections are commonly seen on the surfaces of stars like our sun, where they release tremendous amounts of energy as plasma flares that move in diametrically opposite directions, Comisso said.

While the plasma flares created on stars fall back into the star or jet off into space, the ergosphere of a rotating black hole would mean a falling jet of plasma could acquire negative energy, while its corresponding escaping jet gains additional energy, effectively from the black hole itself, he said.

The new study challenges a 1977 theory for extracting energy from black holes proposed by astrophysicists Roger Blandford and Roman Znajek. They suggested that the magnetic fields near a spinning black hole don’t reconnect, but instead generate additional angular momentum in the escaping plasma jet — a type of “electromagnetic torque.”

Both the new theory and the Blandford-Znajek theory could now be tested to determine which is the most effective for extracting energy from a rotating black hole, Comisso said.

“In the future, people will do supercomputer simulations of both cases and there could be a comparison,” he said. “But at the moment, it is not clear.”

Whichever theory proves correct, it could help astronomers better estimate the spin rate of black holes and quantify the energy given off by plasma jets near their event horizons, he said.

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100,000-year-old story could explain why the Pleiades are called ‘Seven Sisters’

The Pleiades star cluster is also called the Seven Sisters. It may have gotten that name from the oldest story ever told.

People both modern and ancient have long known of the Pleiades, or Seven Sisters, a small collection of stars in the constellation Taurus.

But this famous assembly could point the way to the world’s oldest story, one told by our ancestors in Africa nearly 100,000 years ago, a speculative new study has proposed. To make this case, the paper’s authors draw on similarities between Greek and Indigenous Australian myths about the constellation. But one expert told Live Science that similarities in these myths could be pure chance, not a sign they emerged from a common origin.

The Pleiades are part of what astronomers call an open star cluster, a group of stars all born around the same time. Telescopes have identified more than 800 stars in the region, though most humans can spot only about six on a clear, dark night.

The Pleiades is a small cluster of stars within the Taurus constellation.

Yet cultures around the world have often referred to this constellation with the number seven, calling them the “Seven Sisters,” “Seven Maidens” or “Seven Little Girls.” This head scratcher has puzzled many scientists, such as astrophysicist Ray Norris of Western Sydney University and Commonwealth Scientific and Industrial Research Organisation (CSIRO) Astronomy and Space Science in Australia.

Norris has worked with Indigenous Australians and learned many of their sky stories, including those of different groups who identify the Pleiades as seven girls being chased by the constellation Orion, who is a hunter in these tales. This storyline is extremely similar to the one in ancient Greek legends about these constellations.

“I’ve always thought, ‘Oh that’s really weird,'” Norris told Live Science.

The case isn’t entirely surprising, given that both Orion and the Pleiades are bright and prominent celestial features, and that Earth’s rotation makes it look to us like the former is chasing the latter across the night sky. Some researchers have tried to explain the narrative resemblance through simple cultural exchange, said Norris, given that Europeans arrived in Australia more than two centuries ago. But such a timescale is not long enough for the story to have become so deeply embedded across different, far-flung Australian cultures, he added.

Norris noted that one of the Seven Sisters — a star known as Pleione — is often lost in the glare of a nearby star called Atlas, making it invisible to most human eyes. But 100,000 years ago, when humans were first emerging from the African continent and spreading over the world, the two stars would have been more separated in the night sky, perhaps accounting for why the Pleiades are named for seven beings in many stories. In other words — our ancestors who had not yet left Africa first came up with the tale, then carried this story about the night sky with them as they migrated to Europe, across Asia, and eventually to Australia.

“You’ve got these two bits of circumstantial evidence,” said Norris. “Together they make an interesting hypothesis.” Along with a co-author, he posted a paper Jan. 25 about this possibility to the pre-print database arXiv. Their study has been accepted to, but not yet published in, a peer-reviewed journal.

While noting that it’s a “fun and evocative idea,” astronomer and archaeo-historian Bradley Schaefer of Louisiana State University in Baton Rouge, who was not involved in the work, did not think the explanation likely.

“Humans are humans,” so they will populate the sky with male and female figures. By chance alone, about half the time, you would expect a given constellation to be associated with men, and half the time with women. Which means that “about one-quarter of that time, Orion will be masculine and the Pleiades will be female,” Schaefer said.

Given the huge number of traditional stories, simple coincidences between any given two cultures are likely to crop up, Schaefer said. He also pointed out that the Norris paper used outdated stellar positioning information to model the distance between Pleione and Atlas 100,000 years ago. The correct data places them two times closer during this epoch, meaning there wouldn’t be much significant change in how the constellation appeared to our ancestors.

Norris’ paper doesn’t entirely hinge on this fact, mentioning that the stars in the Pleiades are thought to vary with brightness, and perhaps 100,000 years ago one of the very faint stars was much more visible, though no one knows how much these stars vary in brightness over the long-term.

It’s possible the hypothesis is correct, Schaefer said, but the available evidence isn’t very convincing. It provides a “lesson of what it takes to prove something like this,” he added.

He gave as a counterexample the Big Dipper, another well-known constellation, that cultures across Eurasia describe as a bear. In this case, evidence suggests at least some tales about the Big Dipper likely did emerge from a common origin story, he said.

For instance, in a significant number of these, the “ladle” of the Dipper is given as the body of the bear, and the three stars of the “handle” are identified as its tail (though bears don’t have long tails.)

Yet in many of the traditional stories of Siberian people in Eastern Russia, where people also recognize the Big Dipper as a bear, there is an alteration. The ladle is still the bear’s body, but the three stars of the handle are branded as three hunters chasing the bear. Mizar, the central star of the handle, has a small faint companion known as Alcor, and in the Siberian stories Alcor is a bird helping lead the hunters to the bear, Schaefer said.

A significant number of Native American tales, told by peoples spread across the North American continent north of the Rio Grande, have a very similar setup for the Big Dipper — including the bear, hunters and steering bird, he added. Given that a great deal of other evidence shows that humans migrated over an ancient land bridge in the Bering Strait between modern-day Russia and Alaska thousands of years ago, Schaefer thought it was much more likely that these Big Dipper stories share a common origin.

Even this explanation is not universally accepted by archeo-historians, he added. But the many shared “characteristics mean that it is an evocative, fun, and likely true story,” he said. It might not be the titanic 100,000-year suggested timespan of Orion and the Pleiades, but having a tale that’s at least 14,000 years old is still quite impressive, Schaefer said.

“That makes the Great Bear the oldest intellectual property of humanity,” he said.

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A giant black hole suddenly went dark, and no one knows why

What blotted out GRS 1915+105’s bright light?

Beginning in 2018, one of the brightest X-ray lights in the sky went dark, and scientists still aren’t sure why.

The black hole responsible for creating the lights-out mystery lives in GRS 1915+105, a star system 36,000 light-years from Earth containing both a normal star and the second-heaviest known black hole in the Milky Way. That heavyweight is 10 to 18 times the mass of the sun and second in mass only to Sagittarius A* (or SgrA*), the supermassive black hole in the galactic center. The region around the GRS 1915+105 black hole typically shines with an intense X-ray light, as it feeds on its companion star. As the material circles the cosmic drain, the particles within rub together, generating energy before dropping into the darkness at the black hole’s center. That swirling material is the black hole’s accretion disk, which lights up with X-rays as the black hole devours more and more sustenance.

But researchers saw something surprising beginning in July 2018: The light from the GRS 1915+105 system began to dim. Then, in early 2019, the light dimmed even more, and no one had ever seen anything like it before.

So what’s going on?

“We suggest that this state should be identified as the ‘obscured state,'” the researchers wrote in a new paper published Jan. 1 to the arXiv database, which has not yet been peer-reviewed.

In other words, something has come in between the light source and the Swift X-ray Telescope that’s been monitoring the object, obscuring the telescope’s view.

Plenty of light is still coming from the bright region near the black hole’s event horizon, which astronomer’s sometimes call the “engine,” as well as the larger “accretion disk” of infalling matter. But that light isn’t reaching Earth the way it used to.

“The obscuration geometry” — the precise nature of the structure that’s blocking the light — “is hard to discern,” said lead study author Mayura Balakrishnan, a graduate student in astronomy at the University of Michigan.

No existing telescope can resolve details of the faraway system, so Balakrishnan and her co-authors had to make inferences from how the light coming from GRS 1915+105 changed from day to day between 2018 and 2019.

Black holes with large companion stars sometimes dim because stellar winds from their companions can push clouds of gas in front of their lights.

No existing telescope can resolve details of the faraway system, so Balakrishnan and her co-authors had to make inferences from how the light coming from GRS 1915+105 changed from day to day between 2018 and 2019.

Black holes with large companion stars sometimes dim because stellar winds from their companions can push clouds of gas in front of their lights.

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Could there be a cluster of antimatter stars orbiting our galaxy?

Antimatter shed by anti-stars could even be detectable here on Earth.

Electrons and their antimatter counterparts, positrons, interact around a neutron star in this visualization. Why is there so much more matter than antimatter in the universe we can see?

We don’t know why the universe is dominated by matter over antimatter, but there could be entire stars, and maybe even galaxies, in the universe made of antimatter.

The anti-stars would continuously shed their antimatter components out into the cosmos, and could even be detectable as a small percentage of the high-energy particles hitting Earth.

Unbalanced birth

Antimatter is just like normal matter, except not. Every single particle has an anti-particle twin, with the exact same mass, exact same spin and exact same everything. The only thing different is the charge. For example, the anti-particle of the electron, called the positron, is exactly like the electron except that it has positive electric charge.

Our theories of fundamental physics point to a special kind of symmetry between matter and antimatter — they mirror each other almost perfectly. For every particle of matter in the universe, there ought to be a particle of antimatter. But when we look around, we don’t see any antimatter. Earth is made of normal matter, the solar system is made of normal matter, the dust between galaxies is made of normal matter; it looks like the whole universe is entirely composed of normal matter.

There are only two places where antimatter exists. One is inside our ultra-powerful particle colliders: When we turn them on and blow up some subatomic stuff, jets of both normal and antimatter pop out. The other place is in cosmic rays. Cosmic rays aren’t really rays but rather are streams of high-energy particles streaking in from across the cosmos and hitting our atmosphere. Those particles come from ultra-powerful processes in the universe, like supernovae and colliding stars, and so the same physics applies.

But why is antimatter so rare? If matter and antimatter are so perfectly balanced, what happened to all the anti-stuff? The answer lies somewhere in the early universe.

The anti-galaxy

We’re not exactly sure what did it, but something went off balance in the young cosmos. Presumably in the good old days (and I’m talking when the universe was less than a second old here), matter and antimatter were produced in equal amounts. But then something happened; something caused more matter to be produced than antimatter. It wouldn’t take much, just a one part per billion imbalance, but it would be enough for normal matter to come to dominate essentially the entire universe, eventually forming stars and galaxies and even you and me.

But whatever that process was — and I should mention that the detailed physics of that antimatter-killing mechanism in the early universe are currently beyond known physics, so there’s a lot up in the air here — it may not have been entirely perfect. It’s totally possible that the early universe may have left large clumps of antimatter alone, floating here and there throughout the universe.

Those clumps, if they survived long enough, would grow up in relative isolation. Sure, when matter and antimatter collide, they annihilate each other in a flash of energy, and that would’ve caused some headaches in the early universe, but if the antimatter clumps made it through that trial, they would’ve been home free.

Over the course of billions of years, those clumps of antimatter could have assembled together and grown larger. Remember that the only difference between antimatter and matter is their charge — all other operations of physics remain exactly the same. So you can form anti-hydrogen, anti-helium, and anti-all-the-other-elements. You can have anti-dust, anti-stars fueled by anti-fusion, anti-planets with anti-people drinking refreshing anti-glasses of anti-water, the works.

Counting backward

Astronomers don’t suspect that there are entire anti-galaxies floating around out there, because their interactions with normal matter (say, when two galaxies collide) would release quite a bit of energy — enough for us to notice by now. But smaller clumps could be possible. Smaller clumps like globular clusters.

Globular clusters are small, dense clumps of fewer than a million stars orbiting larger galaxies. They are thought to be incredibly old, as they are not forming new stars in the present epoch, and are instead filled with small, red, aged populations. They are also relatively free of gas and dust — all the fuel you need to make new stars. They just sort of hang around, orbiting lamely around their larger, more active cousins, remnants of a bygone and largely forgotten era. The Milky Way itself has a retinue of about 150 of them.

And some of them may be made of anti-stars.

A team of theoretical astrophysicists calculated what would happen if one of the globular clusters orbiting the Milky Way was actually an anti-cluster, as reported in a paper recently appearing in the preprint journal arXiv. They asked a simple question: what would happen?

Unless the globular cluster plunged right through the disk of the Milky Way, it wouldn’t really blow up. Since the anti-cluster would just be made of stars, and stars don’t take up a lot of volume, there aren’t a lot of opportunities for big booms. Instead, the anti-stars in the anti-cluster would go about their normal lives, doing normal star-like things.

Things like emitting a constant stream of particles. Or having huge flare and coronal mass ejection events. Or colliding with each other. Or dying in fantastic supernova explosions.

All those processes would release tons of antiparticles, sending them flowing out of the anti-cluster and into the nearby volume of the universe, including the Milky Way. Including our solar system, where those antiparticles would appear as just another part of the cosmic ray gang.

So could some of the anti-particles hitting our atmosphere every single day have been launched by an anti-star millions of years ago? Right now it’s too difficult to tell. There are certainly anti-particles mixed in as a part of the total cosmic ray population, but because our galaxy’s magnetic field alters the paths of charged particles (normal and anti alike), it’s hard to tell exactly where a particular cosmic ray actually came from.

But if astronomers are able to pinpoint a globular cluster as a particularly strong source of anti-particles, it would be like opening a time capsule, giving us a window into the physics that dominated the universe when it was only a second old.

We also couldn’t ever visit the anti-cluster, because as soon as we did we would blow up.

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Finally! I’ve had my bags packed for a while.

Potentially habitable exoplanet candidate spotted around Alpha Centauri A in Earth’s backyard

Alpha Centauri A may have its own habitable-zone planet.

This wide-field view of the sky around the bright star system Alpha Centauri was created from photographic images forming part of the Digitized Sky Survey 2.

The nearest solar system to our own may actually host two potentially life-supporting planets, a new study reports.

In 2016, scientists discovered a roughly Earth-size world circling Proxima Centauri, part of the three-star Alpha Centauri system, which lies about 4.37 light-years from Earth. The planet, known as Proxima b, orbits in the “habitable zone,” the range of distances from a star at which liquid water could exist on a world’s surface. (A second planet, Proxima c, was later discovered circling the star as well, but it orbits farther away, beyond the habitable zone’s outer limits.)

There’s considerable debate about the true habitability of Proxima b, however, given that its parent star is a red dwarf. These stars, the most common in the Milky Way, are small and dim, so their habitable zones lie very close in — so close, in fact, that planets residing there tend to be tidally locked, always showing the same face to their host stars, just as the moon always shows Earth its near side. In addition, red dwarfs are prolific flarers, especially when they’re young, so it’s unclear if their habitable-zone worlds can hold onto their atmospheres for long.

The other two stars in the Alpha Centauri trio, however, are sunlike — a pair called Alpha Centauri A and B, which together make up a binary orbiting the same center of mass. And Alpha Centauri A may have its own habitable-zone planet, according to the new research, which was published online today (Feb. 10) in the journal Nature Communications.

The study presents results from Near Earths in the Alpha Cen Region (NEAR), a $3 million project led by the European Southern Observatory (ESO) and Breakthrough Watch, a program that hunts for potentially Earth-like worlds around nearby stars.

NEAR has been searching for planets in the habitable zones of Alpha Cen A and B using ESO’s Very Large Telescope (VLT) in Chile. The NEAR team upgraded the VLT with several new technologies, including a thermal coronagraph, an instrument designed to block a star’s light and allow the heat signatures of orbiting planets to be spotted.

After analyzing 100 hours of data gathered by NEAR in May and June of 2019, the scientists detected a thermal fingerprint in the habitable zone of Alpha Centauri A. The signal potentially corresponds to a roughly Neptune-size world orbiting between 1 and 2 astronomical units (AU) from the star, study team members said. (One AU, the average Earth-sun distance, is about 93 million miles, or 150 million kilometers.)

But that planet has not yet been confirmed, so it remains a candidate for now.

“We were amazed to find a signal in our data. While the detection meets every criteria for what a planet would look like, alternative explanations — such as dust orbiting within in the habitable zone or simply an instrumental artifact of unknown origin — have to be ruled out,” study lead author Kevin Wagner, a Sagan Fellow in NASA’s Hubble Fellowship Program at the University of Arizona, said in a statement.

“Verification might take some time and will require the involvement and ingenuity of the larger scientific community,” Wagner added.

Study co-author Pete Klupar said he hopes the new results will inspire astronomers to study the Alpha Centauri system in greater detail, both via new observing programs and closer scrutiny of archived data, which may hold as-yet unrecognized evidence of the exoplanet candidate.

“It’s like getting a hint in [the board game] Clue,” Klupar, a researcher with Breakthrough Watch’s parent organization, Breakthrough Initiatives, told Space.com. “Now that we’ve got the hint, maybe they can find something.”

And, if the Alpha Centauri A world does indeed exist, it may not be alone.

“In my mind, the most exciting thing about this is, once we find one planet, we tend to find others,” Klupar said.

Even if the Alpha Cen A planet turns out to be a mirage, however, NEAR’s work will not have been in vain, team members said.

“The new capability that we demonstrated with NEAR to directly image nearby habitable-zone planets is inspiring to further developments of exoplanet science and astrobiology,” Wagner said in the same statement.

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Scientists prepare for their last good look at asteroid Apophis before 2029 flyby

Chaos is coming.

An animation shows Apophis’ 2029 path compared to the swarm of satellites orbiting Earth.

On March 5, wave hello to the most infamous asteroid that won’t slam into Earth in 2029. Scientists sure will.

Astronomers first spotted the space rock now known as Apophis in 2004. It’s precisely the sort of object that most humans probably want to know about: It’s awfully big and occasionally comes uncomfortably close to Earth. April 13, 2029, is one such occasion, when Apophis will skim so close to Earth that it will pass through the realm of particularly high-altitude satellites.

(It will not hit Earth. Do not panic. Carry on.)

Scientists are excited. They’ve calculated just how rarely an object this large passes this close to Earth. “This something that occurs about once every 1,000 years, so obviously, it is generating a lot of interest,” Marina Brozović, a radar scientist at NASA’s Jet Propulsion Laboratory in California, told Space.com.

The March flyby won’t be nearly as stunning as the 2029 close approach; Apophis will come only one-tenth of the average distance between the Earth and the sun, more than 40 times as distant as the moon is from Earth. But scientists have big goals for Apophis’ 2029 flyby, and in order to get the most out of that opportunity, they need to know as much as possible about the space rock.

And next month is their last real chance to study Apophis before the big day.

“Apophis in 2029 is going to be a really incredibly observing opportunity for us,” Brozović said. “But before we get to 2029, we are preparing.”

Meet Apophis

Like all near-Earth asteroids, Apophis has been rattling around the inner solar system for millennia, unnoticed by humans. Scientists believe it is more than 1,000 feet (300 meters) wide, around the height of the Eiffel Tower. It’s a mix of rock and metal, according to NASA, and may be shaped a bit like a peanut, two uneven lumps smooshed together.

Astronomers spotted Apophis for the first time in 2004. The asteroid’s discovery is a perfect example of planetary defense, the task dedicated to spotting asteroids around Earth, tracing their precise orbits, and determining whether they pose any risk of hitting Earth. Forewarned is forearmed, so the theory goes, and scientists hope that if they can identify a large future impactor with enough warning, humans can find a way to defend themselves.

And for a brief moment, Apophis seemed to run nearly 3% odds of colliding with Earth on April 13, 2029. (Even the best observations have some uncertainty, and the farther ahead in time an orbit is plotted, the more that uncertainty piles up.) That early concern inspired its name, which refers to an Egyptian “demon serpent who personified evil and chaos,” as NASA puts it.

Some of Apophis’ flybys are perfectly mundane, others quite close. But more precise observations pushed any collision fears first to 2036, then to 2068, when scientists can’t quite positively rule out a collision yet.

If Apophis and Earth ever do collide, hope you aren’t around to see the day. Two asteroids of note have hit Earth in the past century or so. One flattened the Siberian forests of Tunguska in 1908, the other shattered in the skies above Chelyabinsk, Russia, in 2013.

They’re nothing compared to Apophis. “Apophis is 300 times more massive than Tunguska, 5,000 times more massive than Chelyabinsk, so this is an object that certainly gets your attention,” Richard Binzel, a planetary scientist at the Massachusetts Institute of Technology, told Space.com.

A natural experiment

Right now, Apophis is minding its own business like thousands of other pieces of cosmic rubble, trekking around the sun every 323.6 Earth days. Hurtling through space, the asteroid’s existence is utterly uneventful.

That will change.

Nine or so more loops around the sun for Apophis and eight more for Earth will bring the objects just within about 19,800 miles (31,900 kilometers). Scientists know that Apophis will not hit Earth this time. But depending on precisely how the two rocks whiz past each other, Apophis may never look the same.

The same gravity that keeps our mundane lives anchored to Earth’s surface will tug at Apophis throughout the close encounter. Scientists think there’s a chance Earth’s gravity will be strong enough to scatter boulders on the surface of Apophis, or perhaps even stretch the asteroid, as if it were saltwater taffy instead of rock.

How dramatic the stretch will be depends on a host of factors. First, the precise shape of Apophis. Then, its orientation during the flyby: If a broad side faces Earth, each patch feels less gravity; if a narrow head does, the asteroid is set up for a game of tug-of-war. Then, what’s inside: Solid, dense rock would resist Earth’s gravity more, a loose cluster of smaller boulders would give more.

Some of those characteristics scientists can study from Earth. But the interior of Apophis is impenetrable at a distance — except, perhaps, through the 2029 flyby.

“How Apophis itself responds, that’s physically about how Apophis is put together. And that’s something we don’t know — we don’t know how asteroids are put together, we’ve never been able to peer inside an asteroid,” Binzel said. “We see the asteroid outside looking in. This is a chance where we could have the asteroid inside looking out. In other words, is the inside of the asteroid revealing itself by some measurement we can make on the outside?”

It’s an incredible experiment arranged purely by the coincidences of orbits.

Scientists have been here once before. In 1993, astronomers spotted a new comet, dubbed Shoemaker-Levy 9 — only to realize the discovery was in fact a clutch of comet fragments, the debris of a comet that passed too close to massive Jupiter to survive the experience. But the real highlight? Those fragments were on course to slam into the planet the next year.

“The predictions for the impact of Shoemaker-Levy 9 ranged from nothing will happen — it’ll be a dud, a flop — to pretty much parallel to what we actually observed,” Binzel said. “There was enormous uncertainty as to what the outcome of the Shoemaker-Levy 9 impact was going to be simply because it challenged the state of our knowledge. And so the parallel with Apophis is that there is a wide range of predictions for what will happen physically to Apophis itself during the encounter: Apophis might go by the Earth and not care, or Apophis might go by the Earth and be tugged on so significantly that it seismically shakes.”

But in the 1990s, astronomers rallied spacecraft and telescopes alike to gawk at a week of collisions that scarred Jupiter’s clouds for a few weeks. All told, the Shoemaker-Levy 9 observations taught scientists about not just those comet fragments and the icy lump they once made up, but also about Jupiter and its atmosphere.

“I think Apophis is a lot like Comet Shoemaker-Levy 9: It’s an extremely rare natural experiment that we discovered with a short lead time,” Binzel said. “This is something that rarely happens. Nature is doing something amazing for us as a natural experiment, and the challenge is how do we take advantage of that natural experiment.”

And Apophis observations would tell scientists about a different flavor of close encounter than Shoemaker-Levy 9, since Earth’s gravity won’t be strong enough to tear the rock apart.

“It won’t cause this kind of big event but it is still meaningful to understand how the object can be affected by this a-little-bit-distant close flyby,” Yaeji Kim, a doctoral student in aerospace engineering at the University of Auburn in Alabama, told Space.com. “There is no object which has been observed in this kind of phenomenon. From that kind of view, Apophis is a really rare case.”

Preparing for 2029

Making the most of the 2029 flyby will rely on baseline data: what scientists know about Apophis before its dramatic encounter with Earth. That means the observations gathered this year matter. Apophis will be at its closest to Earth this year on March 5 at 8:15 p.m. EST (0115 GMT on March 6).

“Closest” here is a relative term: the asteroid will remain a healthy 0.11 astronomical units (the average distance between the Earth and the sun, or about 93 million miles or 150 million km). That’s nearly 44 times the distance between Earth and the moon.

But that’s close enough for scientists’ most powerful tool for studying asteroids from Earth: planetary radar. Take a powerful radar beam, point it at a mysterious object, then wait. Use a sensitive radio telescope to catch the echo that bounces back, run it through some complicated processing, and the result is a sonogram-like image.

“We like asteroids that come close but, you know, just enough so that we can get a really good signal and we can get really great images,” Brozović said.

With good radar images, scientists can tell, for example what shape an asteroid is: potato, peanut, or even a pair of cherries bound only by gravity. Under particularly friendly circumstances, radar can detect boulders on the surface of a space rock. It also hones scientists’ ability to track an asteroid’s orbit.

Scientists’ top priority while preparing for the 2029 Apophis flyby is sharpening their view of the rock’s shape and its intricate rotations, Binzel said. “We know Apophis is in a very complicated spin state, it’s sort of spinning and tumbling at the same time,” he said. “The 2021 encounter gives us an epoch in time.”

When scientists look to make predictions about what precisely will happen to Apophis during the 2029 encounter, they’ll feed the current best wisdom of the object’s shape and twisted rotation into models — but the resulting predictions will only be as robust as the data.

Inconveniently, Earth lost its most powerful planetary radar system in December, when Arecibo Observatory’s radio telescope in Puerto Rico collapsed. Each radar system has its strengths and weaknesses, and Arecibo would have shone during this preparatory close approach. Without it, scientists aren’t sure how much they’ll be able to improve existing radar observations of Apophis.

But they’ll try, thanks to the planetary radar system at NASA’s Goldstone Deep Space Communications Complex in California, which is due to study Apophis from March 3 to March 14 to cover this flyby. Researchers also hope to use the Green Bank Telescope in West Virginia to catch the echos, rather than having to switch Goldstone’s settings back and forth between send and receive; if they can use two telescopes, the data will be sharper.

“Arecibo was really a powerhouse, the most powerful radar on the planet, so we just can’t make that up,” Brozović said. “But we’re still going to get good data.”

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‘Black Holes: The Edge of All We Know’ documentary dives into a historic photo 1st (exclusive video)

‘Black Holes: The Edge of All We Know’ premieres on March 2.

“We have a goal that’s never been done before: We want to take the first picture of a black hole, something that struggles with all of its might to be unseen.”

The new trailer for the upcoming documentary “Black Holes: The Edge of All We Know” — exclusively provided to Space.com — opens with these words, spoken by Event Horizon Telescope (EHT) founding director Shep Doeleman. As we all know, the international EHT team achieved that audacious goal, capturing an image of the supermassive black hole at the heart of the galaxy M87.

The epic photo captivated the world when Doeleman and his colleagues released it in April 2019, and it continues to resonate today. Indeed, that first direct look at a black hole’s silhouette has become embedded in our culture, serving as a symbol of what humanity is capable of when it aims high and works together.

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This first image of a black hole was revealed by the Event Horizon Telescope, a planet-scale array of eight ground-based radio telescopes forged through international collaboration, in April 2019. It shows the supermassive black hole and its shadow that’s in the center of the galaxy M87.

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Todd

Scientists find first evidence of rare Higgs boson decay

This work provides evidence for something scientists predicted long ago.

Scientists have found the first evidence for a rare type of Higgs boson decay.

Scientists have spotted the first evidence of a rare Higgs boson decay, expanding our understanding of the strange quantum universe.

In 2012, scientists at CERN’s Large Hadron Collider in Switzerland won a Nobel Prize in Physics with a breakthrough finding: they detected the Higgs boson, a subatomic particle predicted by the Standard Model of physics nearly 50 years prior. The Higgs boson doesn’t live very long, quickly decaying into smaller particles like two photons (light particles).

Now, researchers using ATLAS and CMS have found evidence for a rare Higgs boson decay in which the subatomic particle decays into one photon and two leptons, a type of elementary particle that can be charged or neutral. (Electrons and muons, a similar type of subatomic particle, are two examples of charged leptons.) Specifically, they found evidence that the Higgs boson can decay into either a photon and a pair of electrons, or a photon and a pair of muons with opposite charge.

Using the Standard Model, scientists are able to predict the different elementary particles that the Higgs boson can decay into, with a fairly “common” decay being two photons. They can also estimate how often the Higgs boson decays into different combinations of particles, and it is particularly rare for the Higgs boson to decay into a photon and two leptons.

In this type of decay, after its uber-short life, the Higgs boson quickly turns into one photon and what scientists call a “virtual photon.” That “virtual photon,” also known as an “off-shell photon” then immediately turns into something like, in this case, two leptons. This “virtual photon,” has a very small non-zero mass, while regular photons are completely massless, James Beacham, a particle physicist with the ATLAS experiment at the LHC, told Space.com.

In a new study, researchers working with the Large Hadron Collider found the first evidence for a rare Higgs boson decay.

The two leptons “hit our calorimeter really close to each other,” Beacham added. The LHC’s calorimeter is a tool that stops particles coming from a particle collision. Scientists can spot and study these particles when they’re stopped or “absorbed” by the tool.

While scientists have predicted that this type of decay should exist with the Higgs boson, this new detection is “the first hint of evidence of this very rare decay mode of the Higgs boson,” Beacham said.

However, he added, the team likely won’t be able to directly observe the rare decay until they upgrade the facilities for the upcoming High-Luminosity LHC program (which will come following the LHC Run 3. The data used for this study was collected during Run 2, the second running period for the collider that began in 2015 and ended in 2018. Run 3 will begin in March, 2022.)

“With vast amounts of data expected from the High-Luminosity LHC programme, studying rare Higgs boson decays will become the new norm,” according to a statement from ATLAS.

By studying rare decays like this, researchers can explore the possibility of new physics that stretches beyond the Standard Model. The Standard Model explains a lot of things about our physical universe, but it doesn’t include gravity or dark matter, Beacham said. Dark matter, which emits no light and cannot be directly observed, is thought to make up about 80% of all matter in the known universe, but scientists do not yet know exactly what it is.

“We’re always looking for extensions to the Standard Model,” he said. “We have to find a window or a portal from our world into this dark sector world and play experimentally. And one of these could be the Higgs boson.” Beacham explained that the “dark sector” encompasses physics that extends beyond the Standard Model.

Now, don’t get too excited. This paper “does not give us new information yet about the Higgs portal into the ‘dark sector,'” Beacham said. But “this paper proves that we can look for very rare things like this, quite handily,” he said, which pushes the search forward overall.

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Todd

‘Farfarout’ is officially the most distant object in our solar system

Farfarout now has an official designation: 2018 AG37.

It’s official: Farfarout is our solar system’s most distant known object.

The planetoid dubbed Farfarout was first detected in 2018, at an estimated distance of 140 astronomical units (AU) from the sun — farther away than any object had ever been observed. (One AU is the average Earth-sun distance — about 93 million miles, or 150 million kilometers. For perspective, Pluto orbits at an average distance of about 39 AU.)

Farfarout’s inherent brightness suggests a world roughly 250 miles (400 kilometers) wide, barely enough to qualify for dwarf planet status. But the size estimate assumes the world is largely made of ice, and that assumption could change with more observations.

This illustration depicts the most distant object yet found in our solar system, nicknamed “Farfarout,” in the lower right. Along the bottom, various solar system objects are plotted according to their distance from the sun, with the planets and closest dwarf planet (Ceres) appearing at the far left and the most distant solar system objects known on the far right.

And speaking of more observations: The detection team has now collected enough additional data to confirm the existence of Farfarout and nail down its orbit. As a result, the planetoid just received an official designation from the Minor Planet Center in Cambridge, Massachusetts, which identifies, designates and computes orbits for small objects in the solar system.

That designation, announced Wednesday (Feb. 10) in a Minor Planet Center electronic circular, is 2018 AG37. (Farfarout will also receive a catchier official moniker down the road.)

“A single orbit of Farfarout around the sun takes a millennium,” discovery team member David Tholen, an astronomer at the University of Hawai’i, said in a university statement. “Because of this long orbital period, it moves very slowly across the sky, requiring several years of observations to precisely determine its trajectory.”

This artist’s illustration imagines what the distant object nicknamed “Farfarout” might look like in the outer reaches of our solar system. The most distant object yet discovered in our solar system, Farfarout is 132 astronomical units from the sun, which is 132 times farther from the sun than Earth is.

Astronomers spotted Farfarout using the Subaru 8-meter (26.2 feet) telescope on Maunakea in Hawai’i and traced its orbit using the Gemini North and Magellan telescopes.

“Only with the advancements in the last few years of large digital cameras on very large telescopes has it been possible to efficiently discover very distant objects like Farfarout,” co-discoverer Scott Sheppard, a solar system small bodies scientist at the Carnegie Institution for Science, said in the same university statement.

Farfarout is currently about 132 AU from the sun, the researchers determined. And its orbit is now known to be very elliptical, swinging between extremes of 27 AU and 175 AU, thanks to gravitational sculpting by Neptune.

“Farfarout was likely thrown into the outer solar system by getting too close to Neptune in the distant past. Farfarout will likely interact with Neptune again in the future, since their orbits still intersect,” Chad Trujillo, an exoplanet astronomer at Northern Arizona University, said in a statement from the National Science Foundation’s NOIRLab. (The laboratory’s name reflects an acronym no longer used by NSF.)

Because Neptune plays such a large role in Farfarout’s life, the planetoid likely cannot help astronomers in the hunt for Planet Nine, the big hypothetical world that some astronomers think lurks unseen in the far outer solar system.

Planet Nine’s existence has been inferred from its putative gravitational influence on small bodies very far from the sun, whose orbits cluster in odd and interesting ways. But the small worlds that astronomers look to as bread crumbs in the Planet Nine search are free of Neptune’s influence, unlike Farfarout, the researchers said.

The team that spotted Farfarout is well known for peering deep into the dark and frigid outer solar system. For example, in 2018, the researchers also found the distant object Farout and a faraway dwarf planet nicknamed “The Goblin.”

And just to be clear: Farfarout’s distance record refers to its current location. There are a number of other objects, such as the dwarf planet Sedna, whose orbits take them much farther away from the sun at points than Farfarout will ever get. And scientists think there are trillions of comets in our solar system’s Oort Cloud, which begins about 5,000 AU from the sun.

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[Sean Robinson]

Surprisingly mature galaxy in the infant universe suggests galaxies form faster than we thought

“This galaxy looks like a grown adult, but it should just be a little child.”

Gas and dust (shown in blue and red, respectively) in the galaxy ALESS 073.1 observed when the universe was only 1.2 billion years old.

A distant galaxy in the newborn universe essentially resembles a grown adult when it should just look like a small child, new findings that suggest galaxies may evolve far more rapidly than previously thought.

Galaxies come in a variety of shapes, colors and sizes. Much remains a mystery about how galaxies formed in the early universe and how they evolved mature features such as rotating disks and central bulges of tightly packed stars. To peer that far back in time, astronomers need to look at light from distant galaxies, but such targets are often too dim to see well.

In the new study, researchers focused on the galaxy ALESS 073.1,. The starlight they detected from this galaxy came from 12.5 billion years ago, when “the universe was 1.2 billion years old, about 10% of its current age,” study lead author Federico Lelli, an astrophysicist at Cardiff University in Wales, told Space.com.

Using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, the scientists analyzed high-quality images they successfully collected of ALESS 073.1’s dust and gas. They used this data to model how matter was concentrated in the galaxy and calculate its motions.

Unexpectedly, the researchers discovered the galaxy possessed both a rotating disk and a central bulge. They also found signs it may even possess the same kind of spiral arms that mature galaxies such as the Milky Way have extending from their cores.

“This galaxy looks like a grown adult, but it should just be a little child,” Lelli said.

ALESS 073.1’s core also generated more energy than can be explained by stars. Prior work has suggested that such an “active galactic nucleus” (AGN) hints at the presence of a supermassive black hole millions to billions of times the mass of the sun.

Previously, researchers thought central bulges formed slowly over time, due to gravitational instabilities within a galaxy, or mergers between galaxies. “ALESS 073.1, instead, was able to form a big bulge, making up about half of its stars, in less than 1.2 billion years,” Lelli said. “This young galaxy appears surprisingly mature.”

This map shows the motion of gas in the galaxy ALESS 073.1. Gas shown in blue is moving toward us, while the gas shown in red is moving away from us, which suggests the galaxy is rotating.

Earlier research also suggested that galaxies forming in the primordial universe are generally expected to be chaotic, turbulent and largely unstructured because of all the activity they are going through, such as devouring gas from their surroundings and forming stars at very high rates. The orderly structure detected within ALESS 073.1 “is at odds with these expectations,” Lelli said.

These new findings suggest that galaxies can form mature features such as disks and bulges far more quickly and efficiently than previously thought. “Structures like bulges, regular rotating disks, and possibly spiral arms must form in less than one billion years, which is a tall order for current models of galaxy formation,” Lelli said.

In the future, the scientists aim to collect similar high-quality images for a dozen or so more galaxies from the same cosmic epoch, Lelli said.

“These new observations will establish whether galaxies like ALESS 073.1 are the rule or the exception in the primordial universe,” Lelli said. “The observations were supposed to take place last year, but unfortunately the ALMA observatory was shut down due the COVID-19 emergency.”

• This reply was modified 3 years, 11 months ago by Sean Robinson.

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Todd

Mystery of gamma radiation solved: Hidden cannibal star is just having dinner

Don’t get too close to this redback.

An illustration shows the orbits of PSR J2039-5617 and its companion.

The mystery at the heart of an unexplained, bright point of gamma-ray light in the sky has been solved: There’s a deadly spider star flaying a second, wimpier star to bits, sending out rapid-fire bursts of gamma radiation in the process

“Black widows” and “redbacks” in astronomy, as Live Science previously reported, are species of neutron stars — the ultradense remnant cores of giant stars that exploded. Some neutron stars, called pulsars, rotate at regular intervals, flashing like lighthouses. The fastest-spinning among them are millisecond pulsars. When a millisecond pulsar is locked in a rare, tight orbit with a lightweight star, it slowly shreds its partner to bits with each rotation. These binary cannibals are known as black widow or redback stars. Now, with the help of citizen scientists, a team of researchers has revealed a new redback at the heart of a bright system known as PSR J2039–5617.

Since its discovery in 2014, researchers have suspected that PSR J2039–5617 contained a millisecond pulsar and a second star. The bright source of X-rays, gamma rays and visible light closely matched the expected traits of such a system. But proving it required scads of telescope data and more number-crunching than a typical desktop computer could do in a century.

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You have never seen Jupiter like you have in this incredible photo

NASA is no stranger to capturing absolutely stunning images of planets in our solar system, and this time around, the space agency is highlighting Jupiter.

Jupiter is the largest planet in our solar system, and being a gas giant, the surface can show off some incredible storms with some beautiful combinations of colors. Since 2016, NASA’s June spacecraft has been orbiting Jupiter, and throughout that time, the satellite has managed to capture some stunning photos of the distant giant planet.

On the NASA website, NASA has detailed what we see in the image that can be found here. NASA says that “scientists discovered that Jupiter’s powerful atmospheric jet streams extend far deeper than previously imagined.” Additionally, NASA also points out the Great Red Spot, which can be seen on the horizon. If you are interested in reading more about this story, visit this link here.

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Todd

Particles zipping around Earth at near light-speed finally explained

The electrons are trapped in an endless loop around the planet.

An illustration of Earth’s Van Allen belts, with the trajectories of ultra-relativistic electrons in gray. The colorful loops in the foreground are the orbits of satellites that must pass through this electromagnetically dangerous area of space.

In the swirl of a perfect solar storm, electrons can get trapped near Earth, where they can accelerate to nearly the speed of light.

These electrons get their zip from surfing on waves of super-heated, charged gas called plasma that gets launched from the sun during solar storms. They accelerate to near-light speed, though, only when the plasma density is low, according to a new study led by researchers from the GFZ German Center for Geosciences in Potsdam.

The findings are important because electrons traveling so quickly are particularly dangerous to satellites and other electronic equipment. They can penetrate the shielding that protects satellites from other charged particles in solar storms, damaging sensitive components.

The phenomenon occurs in the two Van Allen radiation belts, which are loops of charged particles trapped in a kind of donut shape around Earth. The belts, which extend from about 400 miles to more than 36,000 miles (640 to 58,000 kilometers) above Earth’s surface, protect our planet from charged particles emanating from the sun. But they also react to solar storms in ways that aren’t fully understood. In 2012, NASA launched two Van Allen Probes to take measurements in this mysterious zone of near-space. The probes detected electrons at “ultra-relativistic energies” — in other words, traveling near the speed of light.

Researchers weren’t sure how the electrons were becoming so energetic; some thought that the electrons must be accelerating in two stages, first on a journey from outside the outer reaches of the belts and then again deep inside them. But new data from the Van Allen Probes found that two stages aren’t needed. Instead, the electrons’ speed has everything to do with the density of background levels of plasma during a solar storm.

“This study shows that electrons in the Earth’s radiation belt can be promptly accelerated locally to ultra-relativistic energies, if the conditions of the plasma environment — plasma waves and temporarily low plasma density — are right,” study co-author Yuri Shprits, a space physicist at GFZ Potsdam, said in a statement.

Typically, the density of plasma within the Van Allen belts might be between 50 and 100 particles per cubic centimeter. But when the density drops to less than 10 particles per cubic centimeter, electrons can draw energy from electromagnetic waves known as “chorus waves,” boosting their kinetic energy from a few hundred thousand electron volts to 7 million electron volts. (For comparison, the linear accelerator used up to 2020 at CERN accelerates protons up to 50 million electron volts.) Researchers already suspected the chorus waves might be the culprit for accelerating the electrons, but had not previously realized that this could only happen when plasma density was so low. The low density seems to allow more efficient transfer of energy from the waves to the electrons.

These density drops don’t happen very often, the researchers wrote in their paper, published Jan. 29 in the journal Science Advances. In 2015, when the observations were taken, the right conditions appeared only a “handful” of times, they added. These extreme conditions may have something to do with prolonged convection in the Van Allen belts, which is when when hotter, lighter material is rising and denser, cooler material is sinking, the researchers wrote, but more study is needed to find out why the plasma occasionally thins so much.

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Superpowerful ‘oscillon’ particles could have dominated the infant universe, then vanished

Abstract illustration of the early universe and quantum physics.

A weird, super-powerful particle that’s not truly a particle could have dominated the universe when it was just a second old, releasing a flood of ripples that permeated all of space-time.

Called oscillons, they would have been so energetic their “ripples” could have unleashed so-called gravitational waves — those vibrations in the fabric of space-time that are generated when monster black holes slam into each other. Future experiments to detect these early-universe gravitational waves could give us insights into the most extreme conditions that the universe has ever encountered.

Make it big

Physicists believe that when the universe was very young, it got much, much bigger in a short amount of time. We call this dramatic event “inflation,” and it was perhaps the defining event of the infant cosmos. Sometime within the first fraction of a second of the universe’s existence, something happened (we’re not exactly sure what) that drove the expansion rate to supercritical levels, ballooning the universe to be at least 10^52 times (or 1 followed by 52 zeros) larger than it was before.

After the inflation event, something else happened (again, we’re not exactly sure what) to wind things down and resume a more sedate expansion rate (one that has continued to the present day).

Cosmologists are pretty sure this super-fast ballooning happened in the early universe because today the universe is remarkably uniform at very large scales. A rapid expansion could have done the trick — smoothing out all the wrinkles.

Additionally, astronomers have spotted indirect evidence for the inflation event. Inflation didn’t just make the universe “go big and go home.” It also spurred another event called reheating. Whatever triggered inflation eventually died, but as it faded from the cosmological scene the inflation-causing mechanism released its remaining pent-up energy, transforming this mysterious trigger into a flood of particles that would eventually combine to form protons and neutrons,, atoms, molecules, stars, planets and you.

At the same time, as everything in the universe was mushrooming out during inflation, so too were tiny quantum fluctuations in space-time, which stretched into macroscopic differences — significant bumps and wiggles in the fabric of space-time; these quantum fluctuations meant that some places in the universe had more gravitational attraction than average. In turn, the places of stronger gravity collected bits of material, and those bits of material grew over billions of years, forming the seeds for all the large structures that we see in the cosmos today.

And if inflation was capable of all that, it could have generated even stranger things.

Give it a shake

As for what spark started the inflation event, physicists have several ideas, one of which involves a quantum phenomenon called scalar fields that extends across all of space and time. A scalar field is basically a fancy way of saying that at every point in the universe this field has a value or strength, but no particular direction (to help you visualize this, when you see a temperature map on the local weather forecast, you’re looking at a scalar field). In the modern universe, scalar fields are basically bit players. But the early universe was a much different place, and scalar fields that are rare now could have been in abundance back then. Indeed, some theories of inflation suggest that it was some scalar field that did all the expansion work.

You can think of a scalar field like the surface of the ocean. It extends to all sides and out to the horizon, and it has various waves churning across it. Just like in the ocean, waves in a scalar field can sometimes be calm and regular, and sometimes they are erratic and violent.

According to a new paper published in December 2020 in the preprint database arXiv, that’s exactly what may have happened in the extremely early universe. Shortly after inflation happened, right as reheating was kicking in and the universe was getting flooded with particles, any random scalar fields hanging around could have been disturbed, like a hurricane opening up above the Atlantic.

This could have generated “oscillons,” which are stable waves that can live for a long time. Oscillons happen in all sorts of situations; for instance, a solitary traveling wave is a kind of oscillon. When oscillons form within quantum scalar fields, they also generate their own kind of unique particles.

See what happens

Those oscillons don’t really participate directly in any particle interactions, but the oscillons themselves can still affect the universe. The oscillons would have sloshed around the young universe, and for a brief time the energy contained in the oscillons could have been stronger than the energy contained in any other field or family of particles.

With all that sloshing and waving, interesting things are bound to happen. In the case of oscillons, the sloshing could have generated gravitational waves, which are vibrations in the fabric of space-time itself. As the oscillons wave back and forth throughout the cosmos, their extreme energies distort space-time, generating the gravitational wrinkles.

Long after the oscillons fade away, the gravitational waves can remain, rippling throughout the cosmos to the present day. While we can’t yet observe gravitational waves from the early universe, upcoming detectors like LISA (the Laser Interferometer Space Antenna) and BBO (the Big Bang Observatory) should be able to.

If this oscillon picture is correct, this is one potential mechanism for inflation to generate gravitational waves. If we then see those waves, we will get a view directly into the universe when it was under a second old.

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Todd

Touchdown! NASA’s Perseverance rover lands on Mars to begin hunt for signs of ancient life

The most advanced robot ever sent to Mars has landed successfully.

You can exhale now: NASA’s Perseverance rover has landed safely on Mars.

The car-sized Perseverance, the most advanced robot ever sent to the Red Planet, aced its “seven minutes of terror” touchdown this afternoon (Feb. 18), alighting gently on an ancient lakebed inside the 28-mile-wide (45 kilometers) Jezero Crater shortly before 4 p.m. EST (2100 GMT).

After a series of instrument and hardware checkouts, Perseverance will start doing what it crossed interplanetary space to do: hunt for signs of ancient Mars life, collect and cache rock samples for future return to Earth and demonstrate some shiny new exploration technologies, among other things.

“I don’t think we’ve had a mission that is going to contribute so much to both science and technology,” NASA Acting Administrator Steve Jurczyk told Space.com earlier this week . “It’s going to be truly amazing.”

The first image from the Perseverance Mars rover displayed in mission control minutes after landing on Feb. 18, 2021.

Persevering through a pandemic

Perseverance, the heart of NASA’s $2.7 billion Mars 2020 mission, lifted off from Florida’s Space Coast atop a United Launch Alliance Atlas V rocket on July 30, 2020.

That was about halfway through Perseverance’s month-long launch window, which closed in mid-August. Such windows come along just once every 26 months for Mars missions, so NASA was determined to get the rover off the ground on time — a challenging task made even tougher by the coronavirus pandemic, which forced a rethink of assembly and testing protocols and made it harder for the team to travel.

“In March and early April, we weren’t sure we were going to be able to make it,” Jurczyk said. (Back then, the NASA chief was Jim Bridenstine, and Jurczyk led the agency’s Space Technology Mission Directorate.)

“But we were able to work through the planning and get there,” he added. “It’s a real credit to the dedication and hard work of the team.”

Perseverance personnel in mission control applaud a milestone in the mission’s landing procedure.

The rover’s name is a testament to the spirit that got the mission off the ground and on its way to Mars, agency officials have said.

“Perseverance is a strong word,” Thomas Zurbuchen, associate administrator of NASA’s Science Mission Directorate, said in March 2020 during the rover’s naming ceremony. “It’s about making progress despite obstacles.”

Like NASA’s other Mars rovers, Perseverance got its name via a nationwide student competition. The winning moniker was submitted by Alex Mather, at the time a seventh grader at Lake Braddock Secondary School in Burke, Virginia.

Skycrane redux

The six-wheeled Perseverance is modeled heavily after its predecessor, NASA’s Curiosity rover, which touched down inside Mars’ huge Gale Crater in August 2012 and is still going strong today.

Perseverance is a few inches longer than Curiosity and, with a weight of 2,260 lbs. (1,025 kilograms), nearly 300 lbs. (136 kg) heavier. Some of their scientific instruments are also quite different. But the two rovers share the same basic body plan and the same type of nuclear power source, and they used the same strategy to land safely on the Red Planet.

That strategy, which Curiosity pioneered, sounds like something out of science fiction. Perseverance hit the Martian atmosphere at about 12,100 mph (19,500 kph) and deployed a 70.5-foot-wide (20.5 meters) parachute a few minutes later, while still traveling faster than the speed of sound.

But Mars’ air is just 1% as thick as that of Earth, so a chute couldn’t slow the rover down enough for a safe landing. Mars 2020 therefore employed a rocket-powered sky crane, which lowered the Mars car to the red dirt on cables, then flew off to crash-land intentionally a safe distance away.

NASA received word that Perseverance had gotten down safely at 3:55 p.m. EST (2055 GMT) today, about 11 minutes after the landing actually took place. (It currently takes that long for signals to travel from the Red Planet to Earth.) The news prompted wild celebrations at the Jet Propulsion Laboratory (JPL) in Southern California, which manages the Mars 2020 mission.

There was doubtless a decent dose of relief mixed in with the excitement, for success today was far from guaranteed. Over the decades, only about half of Mars surface missions have touched down safely. And Perseverance’s landing site on Jezero’s floor, which features hazards such as cliffs, sand dunes and boulder fields, was the toughest ever targeted by a Mars mission, NASA officials have said.

Indeed, this dangerous terrain required Perseverance to make the most precise Red Planet touchdown ever. The rover’s landing ellipse was just 4.8 miles long by 4.1 miles wide (7.7 by 6.6 kilometers), compared to 4 miles by 12 miles (7 by 12 km) for Curiosity.

Perseverance hit that target today with the aid of two new entry, descent and landing (EDL) technologies that Curiosity didn’t have at its disposal. One, called “range trigger,” allowed the mission to deploy its supersonic parachute at just the right moment. The other, “terrain-relative navigation,” enabled Perseverance’s sky crane to assess the Jezero landscape and navigate autonomously around potential hazards during the descent.

These landing technologies worked exactly as planned, guiding Perseverance to a picture-perfect touchdown on a safe, flat part of Jezero’s floor, mission team members said during a post-landing news conference this afternoon.

And the rover seems to have made it through EDL in fine shape. Perseverance has already beamed home its first images of its new surroundings, and initial health checks revealed no causes for concern.

“The power system looks good,” Mars 2020 deputy project manager Jennifer Trosper, also of JPL, said during today’s briefing. “The batteries are charged at 95%, and everything looks great.”

Looking for Mars life

Curiosity is a habitability-assessing mission, and that rover has found plenty of evidence that Gale Crater could have supported Earth-like life billions of years ago. Perseverance will take the next step, actively searching for signs of past organisms in the first life hunt conducted on the Martian surface since NASA’s twin Viking landers ceased operations in the early 1980s. (The Vikings looked for present-day Mars life, however, whereas Perseverance is focused on the distant past.)

Jezero is a great place to do such work, mission team members have said. The crater, which lies about 18 degrees north of the Martian equator, hosted a lake the size of Lake Tahoe long ago and also sports an ancient river delta. In addition, Mars orbiters have spied on Jezero’s floor clay minerals, which form in the presence of liquid water.

Perseverance will scrutinize Martian dirt and rock with a variety of high-tech science gear, including multiple spectrometers, high-resolution cameras and ground-penetrating radar. One of the rover’s seven instruments, called SuperCam, will zap rocks with a laser and gauge the composition of the resulting vapor.

Such observations could potentially identify a convincing sign of ancient Mars life — perhaps something akin to stromatolites, structures created here on Earth by dirt-trapping microbial mats. But that’s a tall order for a lonely robot far from home. A positive ID of Martian life, if it ever existed, will likely require analyses by advanced equipment in laboratories here on Earth, NASA officials have said. And Mars 2020 aims to help make that happen.

A Mars sample-return campaign begins

Using the drill at the end of its long robotic arm, Perseverance will collect about 40 samples from especially promising sites and seal them inside special tubes. This material will then be brought back to Earth by a joint NASA-European Space Agency campaign, perhaps as early as 2031.

Once here, the samples will be studied in countless ways by hundreds of scientists for decades to come. Researchers are still poring over the moon rocks hauled home by NASA’s Apollo astronauts half a century ago, after all, and that material has no serious astrobiological potential.

“Mars sample return is the planetary science endeavor of our generation,” Bobby Braun, director of solar system exploration at JPL, said during a pre-landing news conference yesterday (Feb. 17).

“It’s ambitious. It’s challenging. It’s a scientifically compelling goal that, over decades, we have been working toward,” Braun said. “And it’s right there. It’s just within our reach.”

Demonstrating future exploration tech

Mars 2020 will also pave the way for more ambitious exploration of the Red Planet in the future, if all goes according to plan.

For example, one of Perseverance’s instruments, called MOXIE (“Mars Oxygen ISRU Experiment”), is designed to generate oxygen from the Red Planet’s atmosphere, which is 95% carbon dioxide by volume. Such equipment, if scaled up, could help humanity get a foothold on Mars down the road, NASA officials have said. (“ISRU,” by the way, is short for “in situ resource utilization,” a fancy term for living off the land.)

And attached to Perseverance’s belly is a 4-lb. (1.8 kg) helicopter named Ingenuity, which will attempt to become the first rotorcraft ever to fly in the skies of a world beyond Earth. If Ingenuity succeeds, helicopters could soon become an important part of the Mars-exploration toolkit.

“We could put sensors on them and use them as science platforms, and also as scouts,” Jurczyk said. Aerial reconnaissance by rotorcraft could allow rovers to “drive more autonomously, and drive faster and longer on the surface,” he added.

An artist’s concept of NASA’s Ingenuity helicopter flying on Mars.

Ingenuity will get to strut its stuff soon. The little helicopter will conduct its few test flights very early in the mission, shortly after the Mars 2020 team assesses the condition of the rover and calibrates its science instruments. Perseverance will roll a safe distance away before Ingenuity lifts off, but the rover might still be able to document the flights — perhaps with its cameras or its two microphones.

Those two mics — which are part of SuperCam and the EDL subsystem, respectively — are another groundbreaking aspect of Mars 2020: No mission has ever successfully captured true audio on the Red Planet’s surface. So, if either mic is able to record some Martian sounds, Perseverance will bring this alien world to life for us in a new way.

These initial activities — the checkouts and Ingenuity’s demonstration flights — will likely take several months, Mars 2020 team members have said. Perseverance will then be ready to start its main science work, the hunt for biosignatures and the collection of samples.

The mission team has already mapped out a tentative traverse for Perseverance. If all goes according to plan, the rover will start its studies in Jezero’s delta region, then move toward ancient lakeshore environments and eventually climb up onto the crater’s rim, which sits several thousand feet above its floor.

“This will allow us to come up with the best possible set of samples to be brought back to Earth, to answer the major questions that we have about Mars and about life,” Mars 2020 project scientist Ken Farley, who’s based at JPL, said during a news conference last month.

The envisioned traverse is about 15 miles (25 km) long and will take Perseverance a number of years to complete, Farley added. The rover’s prime mission lasts just one Mars year (about 687 Earth days), so Mars 2020 would need some extensions and continued good health to make it all the way to Jezero’s rim.

But there’s reason to be hopeful that it can happen. After all, Curiosity is well into its ninth Earth year exploring Gale, about 2,300 miles (3,700 km) from Perseverance’s new digs.

Perseverance’s landing came just a week after two other Mars missions reached the Red Planet. The United Arab Emirates’ Hope probe and China’s Tianwen-1 mission slipped into Mars orbit on Feb. 9 and Feb. 10, respectively, landmark achievements for both nations. Hope will remain in orbit, as will one component of Tianwen-1. But the Chinese mission will also put a rover duo down on the Martian surface, likely in May.

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End of Neanderthals linked to flip of Earth’s magnetic poles, study suggests – TheGuardian.com

Event 42,000 years ago combined with fall in solar activity potentially cataclysmic, researchers say

When the poles switch, Earth’s magnetic field weakens dramatically, exposing the planet to cosmic radiation.

The flipping of the Earth’s magnetic poles together with a drop in solar activity 42,000 years ago could have generated an apocalyptic environment that may have played a role in a major events ranging from the extinction of megafauna to the end of the Neanderthals, researchers say.

The Earth’s magnetic field acts as a protective shield against damaging cosmic radiation, but when the poles switch, as has occurred many times in the past, the protective shield weakens dramatically and leaves the planet exposed to high energy particles.

One temporary flip of the poles, known as the Laschamps excursion, happened 42,000 years ago and lasted for about 1,000 years. Previous work found little evidence that the event had a profound impact on the planet, possibly because the focus had not been on the period during which the poles were actually shifting, researchers say.

Now scientists say the flip, together with a period of low solar activity, could have been behind a vast array of climatic and environmental phenomena with dramatic ramifications. “It probably would have seemed like the end of days,” said Prof Chris Turney of the University of New South Wales and co-author of the study.

The team have collectively termed this period “the Adams event”, a nod to Douglas Adams, the author of the Hitchhiker’s Guide to the Galaxy in which 42 was said to be the “answer to the ultimate question of life, the universe and everything”.

Writing in the journal Science, Turney and his colleagues describe how they carried out radiocarbon analyses of the rings of ancient kauri trees preserved in northern New Zealand wetlands, some of which were more than 42,000 years old.

This allowed them to track over time the rise in carbon-14 levels in the atmosphere produced by increasing levels of high energy cosmic radiation reaching the Earth during the Laschamps excursion. As a result they were able to date the atmospheric changes in more detail than offered by previous records, such as mineral deposits.

They then examined numerous records and materials from all over the world, including from lake and ice cores, and found that a host of major environmental changes occurred at the same time as the carbon-14 levels peaked.

“We see this massive growth of the ice sheet over North America … we see tropical rain belts in the west Pacific shifting dramatically at that point, and then also wind belts in the southern ocean and a drying out in Australia,” said Turney.

The researchers also used a model to examine how the chemistry of the atmosphere might change if the Earth’s magnetic field was lost and there was a prolonged period of low solar activity, which would have further reduced Earth’s protection against cosmic radiation. Ice core records suggest such dips in solar activity, known as the “grand solar minima”, coincided with the Laschamps excursion.

The results reveal that the atmospheric changes could have resulted in huge shifts in the climate, electrical storms and widespread colourful aurora.

As well as the environmental changes potentially accelerating the growth of ice sheets and contributing to the extinction of Australian megafauna, the team suggest they could also be linked to the emergence of red ochre handprints, the suggestion being that humans may have used the pigment as a sunscreen against the increased levels of ultraviolet radiation hitting the Earth as a result of the depletion of ozone.

They also suggest the rise in the use of caves by our ancestors around this time, as well as the rise in cave art, might be down to the fact that underground spaces offered shelter from the harsh conditions. The situation may also have boosted competition, potentially contributing to the end of the Neanderthals, Turney said.

The Earth’s magnetic field has weakened by about 9% over the past 170 years, and the researchers say another flip could be on the cards. Such a situation could have a dramatic effect, not least by devastating electricity grids and satellite networks.

Richard Horne, the head of space, weather and atmosphere at the British Antarctic Survey, who was not involved in the work, said the chemical changes in the upper atmosphere predicted by the study chimed with what had been measured at Halley research station in Antarctica during strong but short-lived events in which energetic particles were emitted from the sun.

But could the environmental effects have been as severe as the team predict? “Maybe not as extreme, but it gives you pause for thought,” said Horne, noting that it was unlikely the Earth’s magnetic field would disappear completely.

Dr Anders Svensson of the University of Copenhagen, however, said that ice cores from Greenland and Antarctica do not show evidence of any dramatic climate change that occurred around the time of the Laschamps excursion, but that did not rule out it having an impact. “Changes in the ozone layer and the impact of increased UV radiation on humans is not something we can confirm or reject from ice cores,” he said.

Chris Stringer, who studies human origins at the Natural History Museum in London, said the work was important. He said the greater use of caves as shelter was plausible, but that the link to a rise in cave art was less convincing because paintings of pigs were apparently being produced in Sulawesi in Indonesia well before the Laschamps excursion.

“The authors also make a link with the physical extinction of the Neanderthals around 40,000 years ago and I think it could certainly have contributed to their demise,” he said. “But they did survive longer and ranged more widely than just Europe, and we have a very poor fix on the timing of their final disappearance across swathes of Asia.”

Dr Richard Staff, a research fellow in quaternary geochronology at the University of Glasgow said the study was exciting, and noted that it could lead to further investigation into the environmental and evolutionary effects of other, larger dramatic downturns in the Earth’s magnetic field strength further back in time.

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[Sean Robinson]

Oh, my heart is broken and I haven’t clicked a link.

Random search, and blammo!

Planet 9 probably doesn’t exist, new paper argues – LiveScience.com

If Planet Nine exists, why has no one seen it? – BBC.com

Evidence of Planet Nine diminishing as researchers find no evidence of clustering – Phys.org

‘Any evidence for Planet Nine is gone’: Scientists dispute probability of mystery planet – CNet.com

Of course it exists you dumb fucks. There’s a picture right there!

• This reply was modified 3 years, 10 months ago by Sean Robinson.

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The case for, and against, the still-unseen Planet 9 – AstronomyNow.com

Planet Nine may NOT exist after all: Unusual orbits detected in the outer solar system may be an ILLUSION, study claims – DailyMail.com

Claim for giant ‘Planet Nine’ at Solar System’s edge takes a hit – Sciencemag.org

Planet Nine Might Be a Giant Illusion, Scientists Say, And Here’s Why – ScienceAlert.com

Evidence for a hidden ‘Planet Nine’ beyond Neptune has weakened – NewScientist.com

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From the Livescience link

Is anything out there?

…But in this new paper, published Feb. 12 to the arXiv database, but not yet peer-reviewed, a large collaboration of researchers suggest that the TNOs aren’t particularly clustered — they just look that way because of where Earthlings are pointing their telescopes. The researchers took a sample of 14 known “extreme” (meaning very distantly orbiting, belonging to the family of objects that has most influenced Planet Nine research) TNOs and assumed they were part of a mostly unseen larger family of objects, which they almost certainly are. Then they analyzed how much time telescopes had spent pointing at different parts of the sky. They found that astronomers might detect this particular collection of objects if all the TNOs on the outermost fringes of the solar system actually had a fairly uniform distribution — anywhere from 17% to 94% uniform. (A 100% uniform distribution would mean that TNO orbits are evenly spaced around the sun.) In other words, the extreme TNOs (ETNOs) might seem to be clustering, but that’s only because telescopes have, on average, concentrated their attention on that part of space. Such uniform distribution would not fit the Planet Nine hypothesis.

This statistical analysis is similar to the sort of gut checks opinion pollsters do all the time. If a survey of a few hundred Americans found that country music was the favored genre of 55% of people, but then a closer look at the data revealed that 40% of respondents happened to be from Nashville, the pollster might adjust the data to account for the fact that that the sample was so heavily weighted toward one area of the country. In doing so, the pollster might find that the huge preference for country music disappears.

Dave Tholen, a University of Hawaii astronomer who searches for TNOs using the Subaru telescope on the summit of Mauna Kea in Hawaii, and who was not involved in the study, said there’s still too little data for anyone to be drawing any firm conclusions about Planet Nine.

“We have a classic situation that I might describe as ‘the statistics of small numbers.’ One discovery can’t align with anything. Two aligned orbits could easily be a coincidence. Three aligned orbits might raise the question, but certainly isn’t enough on which to hang your hat,” Tholen told Live Science in an email. “How many aligned orbits do you need before the chances of it being a coincidence drop to a convincingly small number? And what constitutes ‘alignment’? Do they need to be within 10 [degrees] of each other? 30 [degrees]? 90 [degrees]? My own feeling is that we’re still in the ‘suggestive’ stage.”

The clustering of TNOs suggests there might be a planet tugging on them, making it a hypothesis worth exploring. But the clustering seen so far is not strong evidence. On the flip side, the new study can’t rule out Planet Nine either, Tholen said.

Efforts underway right now will dramatically expand the catalog of known TNOs, and provide firmer ground for any claims on the subject, Tholen said.

“Progress comes slowly,” he said. “Any paper reporting on simulated surveys will always be out-of-date as long as we continue our observational work, because they won’t include our latest sky coverage.”

His team, Tholen said, works to observe the sky uniformly “specifically to avoid the sort of… bias” at the heart of the new paper’s argument.

Scott Sheppard, an astronomer who studies TNOs at the Carnegie Institution for Science in Washington, D.C., and was one of the first researchers to propose that a large planet might exist in the far-outer solar system, largely agreed with Tholen’s take.

“We just do not have enough bona-fide distant ETNOs to have a good statistical argument for or against the clustering,” he told Live Science.

The new paper ignores certain well-studied objects, like Sedna, and said that this makes the results less convincing, Sheppard noted. And some of the objects the new paper studied are likely influenced by Neptune’s gravity, making them bad candidates for studying Planet Nine, he added.

“I would say we need to triple the current sample size of very distant ETNOs to have reliable statistics on the angles of these object’s orbits,” Sheppard said. “If you do not have a large enough sample size, even if things are strongly clustered, the statistics will still be consistent with a uniform distribution simply because the sample size is too small.”

Kevin Napier, a University of Michigan astronomer and lead author of the new paper, told Science magazine he agreed somewhat with concerns about his paper’s sample size. Napier told Science that the statistical power of their methods is inherently weak with only 14 objects involved, and that when the sensitive Vera C. Rubin Observatory in Chile comes online in 2023, it should reveal hundreds of new TNOs that can shine some light on the Planet Nine question.

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‘Ghostly’ neutrino from star-shredding black hole reveals cosmic particle accelerator of epic proportions

A ghostly particle that smashed into Antarctica in 2019 has been traced back to a black hole tearing apart a star while acting like a giant cosmic particle accelerator, a new study finds.

Scientists investigated a kind of subatomic particle known as a neutrino, which is generated by nuclear reactions and the radioactive decay of unstable atoms. Neutrinos are extraordinarily lightweight — about 500,000 times lighter than the electron.

Neutrinos possess no electric charge and only rarely interact with other particles. As such, they can slip through matter easily — a light-year’s worth of lead, equal to about 5.8 trillion miles (9.5 trillion kilometers) would only stop about half of the neutrinos flying through it.

However, neutrinos do occasionally strike atoms. When that happens, they give off telltale flashes of light, which scientists have previously spotted to confirm their existence.

In the new study, researchers examined an extremely high-energy neutrino they spotted on Oct. 1, 2019, using the IceCube Neutrino Observatory at the South Pole.

After the supermassive black hole in the galaxy 2MASX J20570298+1412165 tore apart the star, roughly half of the star’s debris was flung into space, while the remainder formed a glowing accretion disk around the black hole.

“It smashed into the Antarctic ice with a remarkable energy of more than 100 tera-electronvolts,” study co-author Anna Franckowiak, now at the University of Bochum in Germany, said in a statement. “For comparison, that’s at least 10 times the maximum particle energy that can be achieved in the world’s most powerful particle accelerator, the Large Hadron Collider.”

To discover the origins of such a powerful neutrino, the scientists traced its path through space. They found it likely came from the galaxy designated “2MASX J20570298+1412165” in the constellation Delphinus, the dolphin, and is located about 750 million light-years from Earth.

About six months before scientists detected the high-energy neutrino, astronomers witnessed a glow from this galaxy using the Zwicky Transient Facility on Mount Palomar in California. This light likely came from a black hole shredding a star, a so-called tidal disruption event dubbed “AT2019dsg.”

The researchers suggest a star came too close to a supermassive black hole at the center of the galaxy 2MASX J20570298+1412165, one about 30 million times more massive than the sun. It then got ripped apart by the black hole’s colossal gravity, an extreme version of the way in which the moon causes tides to rise and fall on Earth.

The scientists noted that about half the star’s debris was hurled into space, whereas the other half settled into a swirling disk around the black hole. As matter from this dismantled star fell into this disk, it got hotter and shone brightly enough for astronomers to see from Earth.

The researchers estimated this neutrino only had a 1 in 500 chance of coinciding with the event. This suggested that scientists have likely detected the first particle traced back to a tidal disruption event.

“It was long predicted by theoretical work that neutrinos might come from tidal disruption events,” study lead author Robert Stein, a multimessenger astronomer at the German Electron Synchrotron (DESY) in Zeuthen, Germany, told Space.com. “This work is the first observational evidence to support that claim.” He and his colleagues detailed their findings online Feb. 21 in the journal Nature Astronomy.

The Zwicky Transient Facility captured this snapshot of tidal disruption event AT2019dsg (circled), on Oct. 19, 2019.

These new findings shed light on tidal disruption events, about which much remains unknown. Specifically, the researchers suggested the neutrino came from jets of matter blasting out from near the black hole’s accretion disk at nearly the speed of light, Cecilia Lunardini, a particle astrophysicist at Arizona State University, told Space.com. She and study co-author Walter Winter at DESY detailed their findings online Feb. 22 in a companion study in the journal Nature Astronomy.

Although these relativistic jets likely spewed out many different kinds of particles, these were mostly electrically charged particles, which are deflected by intergalactic magnetic fields before they can reach Earth. In contrast, neutrinos (which have no charge) can travel in a straight line like light rays from the tidal disruption event.

This discovery marks only the second time scientists have traced a high-energy neutrino back to its source, Stein said. The first time, in 2018, astronomers tracked such a neutrino back to the blazar TXS 0506+056, a huge elliptical galaxy with a fast-spinning supermassive black hole at its heart.

“Knowing where high-energy neutrinos come from is a big question in particle astrophysics,” Stein said. “Now we have more proof they can probably come from tidal disruption events.”

One strange aspect of this discovery was how the neutrino was not detected until a half-year after the black hole began gobbling the star. What this suggests is that the tidal disruption event can act like a giant cosmic particle accelerator for months, Stein said.

Although the researchers only detected one neutrino from this tidal disruption event, “for us to detect even one, there must have been billions and billions it was generating,” Stein said. “We got lucky to see one.”

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What is the cosmological constant?

Not a blunder anymore

Artist depiction of a supernova explosion in space. In the 1990s, researchers used supernovae to identify dark energy’s existence, bringing science back to Einstein’s once-discarded cosmological constant.

The cosmological constant is presumably an enigmatic form of matter or energy that acts in opposition to gravity and is considered by many physicists to be equivalent to dark energy. Nobody really knows what the cosmological constant is exactly, but it is required in cosmological equations in order to reconcile theory with our observations of the universe.

Who came up with the cosmological constant?

Albert Einstein, the famous German-American physicist, came up with the cosmological constant, which he called the “universal constant,” in 1915 as a means to balance certain calculations in his theory of general relativity. At the time, physicists believed the universe was static — neither expanding nor contracting — but Einstein’s work suggested that gravity would cause it to do one or the other. So, to mesh with the scientific consensus, Einstein inserted a fudge factor, denoted by the Greek letter lambda, into his results, which kept the cosmos still.

Yet a little over a decade later, the American astronomer Edwin Hubble noticed that galaxies were actually moving away from us, indicating the universe was expanding. Einstein called lambda his “greatest mistake.”

Hubble’s observations negated the need for a cosmological constant for decades, but that changed when astronomers examining distant supernovas in the late 1990s discovered that the cosmos was not only expanding, but accelerating in its expansion. They named the mysterious anti-gravity force required to account for this phenomena “dark energy.”

In the 1920s, Russian physicist Alexander Friedmann developed an equation, now called the Friedmann Equation, which describes the properties of the universe from the Big Bang onward, according to an online tutorial from Georgia State University.

By dusting off Einstein’s lambda and plugging it into the Friedmann equations, researchers could model the cosmos correctly — that is, with an accelerating expansion rate. This version of the Friedmann Equation now forms the backbone of contemporary cosmological theory, which is known as ΛCDM (Lambda CDM, where CDM stands for cold dark matter) and accounts for all the known components of reality.

So, what is this magic number then?

However, no one truly understands what lambda is. Most physicists consider it interchangeable with the concept of dark energy, but that doesn’t make things any clearer because dark energy is simply a placeholder describing some unknown anti-gravity substance. So, we’ve essentially reverted to using Einstein’s fudge factor.

One potential explanation for the cosmological constant lies in the realm of modern particle physics. Experiments have verified that empty space is permeated by countless virtual particles constantly popping in and out of existence. This ceaseless action creates what is known as a “vacuum energy,” or a force arising from empty space, inherent in the fabric of space-time that could drive apart the universe.

This graphic shows a map of the universe’s expansion rates in different directions. The map is in galactic coordinates, with the center looking toward the center of our galaxy. The black and purple colors show the directions of the lowest expansion rates (the Hubble constant); yellow and red show the directions of the highest expansion rates.

But connecting vacuum energy to the cosmological constant is not straightforward. Based on their observations of supernovas, astronomers estimate that dark energy should have a small and sedate value, just enough to push everything in the universe apart over billions of years.

Yet when scientists try to calculate the amount of energy that should arise from virtual particle motion, they come up with a result that’s 120 orders of magnitude greater than what the supernova data suggest.

To add to the conundrum, some researchers have proposed that the cosmological constant might not be a constant at all, but rather changes or fluctuates with time. This theory is called quintessence and some projects, such as the Dark Energy Survey, are currently making precise observations to see if it has any observational support.

In the meantime, cosmologists will continue to use lambda. They may not know what it is, but they know that they need it to make the universe make sense.

Additional resources:

Check out NASA’s page about the cosmological constant.
See a technical explanation of vacuum energy density from UCLA.
The YouTube channel minutephysics explains Einstein’s biggest blunder here.

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Astrophysicists create the most accurate ‘flat map’ of Earth ever

Here are two pancake maps of Earth.

This double-sided pancake map is the most accurate flat map of Earth ever created.

Earth is a sphere, so how can it be accurately portrayed on a 2D map? Simply flatten Earth into two pancakes, one depicting the Northern Hemisphere and the other the Southern, with the equator running around the edge, a new study finds.

These two “pancakes” represent the most accurate flat map of Earth ever made, the study researchers said. Unlike other flat maps, the new circular map doesn’t downsize or supersize the area of certain oceans or landmasses — for instance, many 2D maps depict Greenland as about the same size as Africa, when in fact Africa is 14 times larger, Scientific American reported.

Plus, unlike some retangular maps that are very large, “this is a map you can hold in your hand,” study lead researcher J. Richard Gott, an emeritus professor of astrophysics at Princeton University, said in a statement. “The map can be printed front-and-back on a single magazine page, ready for the reader to cut out.”

Creating accurate 2D maps has dogged cartographers for centuries. To help determine the various problems flat maps face, Gott and study co-researcher David Goldberg, a professor of physics at Drexel University in Philadelphia, created a system to rate existing flat maps, and published their results in 2007 in the journal Cartographica. Their system scored 2D maps on six types of distortions: local shapes, areas, distances, flexion (bending, or curvature distortions), skewness (lopsidedness) and boundary cuts (continuity gaps, like splitting up the Pacific Ocean). Maps that received lower scores were more accurate, they said. Well-designed globes, which are spherical like the Earth, would earn scores of zero.

“One can’t make everything perfect” on a flat Earth map, Gott said. “A map that is good at one thing may not be good at depicting other things.” Take, for example, the world map most people are familiar with — the Mercator projection, a staple found in many classrooms and the basis for Google Maps. While the Mercator projection is good at representing local shapes, it distorts surface areas near the North and South Poles, so these regions are often chopped off, the researchers said.

The Mercator projection, created in 1569 by the Dutch geographer Gerard Mercator, helped sailors navigate the world. Notice that the polar regions are distorted and that Japan and Hawaii look farther apart than they really are.

According to the team’s rating system, the top-rated flat map projection is the Winkel Tripel, a map that originated in 1921, when German cartographer Oswald Winkel proposed it, and which the National Geographic Society now uses. This map drew a low score of 4.563, but it still had a “boundary cut” problem, because it split the Pacific Ocean in two, with one part on the right and the other on the left side of the map. This split creates the illusion that Asia and Hawaii are farther apart than they really are.

The Winkel Tripel projection world map was first designed in 1921. Notice how it distorts Antarctica and creates the illusion that Japan is very far away from California.

To get around this boundary-splitting problem, the researchers approached mapmaking from a new perspective, with the hopes of designing a “flat map with the least error possible,” Gott said. “We’re proposing a radically different kind of map, and we beat Winkel Tripel on each and every one of the six errors.”

The end result, the pancake map, borrowed ideas from previous research on polyhedra, or many-sided 3D shapes. In 1943, the American architect Richard Buckminster Fuller drew outlines of regular shapes that made up a world map, and he wrote instructions for how his map could be folded into a polyhedral globe. But while Fuller did a good job detailing the continents, he wasn’t as exact with the oceans, which introduced errors. For instance, Australia and Antarctica were too far apart on his creation.

In a 2019 study posted to the arXiv database, which has yet to be peer reviewed, Gott considered “envelope polyhedra,” which involved gluing together regular shapes, back-to-back. This led to the idea of a double-sided circular map, he said.

The new map, published Feb.15 to the arXiv database, consists of two pancake maps that can be viewed side-by-side or back-to-back. Either way, the map doesn’t have any boundary cuts. If you want to measure distances from one hemisphere to the other, just use a string or a measuring tape to reach around the side of one pancake to the other, Gott said.

“If you’re an ant, you can crawl from one side … to the other,” Gott said. “We have continuity over the equator. [Africa] and South America are draped over the edge, like a sheet over a clothesline, but they’re continuous.”

The pancake map also has smaller distance errors than any other 2D flat map. For instance, its configuration means distances can’t be more or less than 22.2% of what they are in reality, Gott said. In comparison, the Mercator and Winkel Tripel projections have remarkably high distance errors near the poles and at the left and right edges of the map.

What’s more, areas at the pancake map’s equatorial edge are only 1.57 times larger than areas at the center, the researchers said.

Gott said he’s not aware of any other double-sided pancake Earth. “Our map is actually more like the globe than other flat maps,” Gott said. “To see all of the globe, you have to rotate it; to see all of our new map, you simply have to flip it over.”

Gott and his colleagues have also created pancake-like maps of Mars, Jupiter, the sun and other heavenly bodies, which can be seen here.

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Company plans to start building private Voyager space station with artificial gravity in 2025

Voyager Station will be able to accommodate 400 guests, its builders say.

A visualization of the rotating Voyager Station, which will support scientific experiments and also function as a “space hotel” for tourists.

Orbital Assembly Corporation (OAC) recently unveiled new details about its ambitious Voyager Station, which is projected to be the first commercial space station operating with artificial gravity.

OAC, a manufacturing firm centered on the colonization of space, discussed Voyager Station during a video press junket late last month. The Jan. 29 “First Assembly” virtual event served as an update for interested investors, marketing partners and enthusiastic vacationers hoping to someday book a room aboard the rotating Voyager Station.

The project’s roots go back a number of years.

John Blincow established The Gateway Foundation in 2012. The organization’s plans include jumpstarting and sustaining a robust and thriving space construction industry, first with the Voyager Station and The Gateway commercial space station — “important first steps to colonizing space and other worlds,” the foundation’s website states. OAC was founded by the Gateway Foundation team in 2018 as a way to help make these dreams come true.

The hour-long Jan. 29 presentation and Q&A session was hosted by OAC medical advisor Shawna Pandya and streamed live on the company’s YouTube channel. During the event, the space construction company revealed its schedule for the next chapter of human space exploration.

Its team of skilled NASA veterans, pilots, engineers and architects intends to assemble a “space hotel” in low Earth orbit that rotates fast enough to generate artificial gravity for vacationers, scientists, astronauts educators and anyone else who wants to experience off-Earth living.

As a multi-phase endeavor requiring funds to realize the dream, OAC is now officially open for private investors to purchase a stake in the company at $0.25 per share, until April 1, 2021.

Voyager Station is patterned after concepts imagined by legendary rocket scientist Wernher von Braun, one of the main orchestrators of NASA’s Apollo program. The 650-foot-wide (200 meters) wheel-shaped habitat will spin with an angular velocity high enough to create moon-like levels of artificial gravity for occupants.

Designed by Gateway Foundation executive team member and lead architect Tim Alatorre, Voyager will become the biggest human-made structure in space, fully equipped to accommodate up to 400 people. Assembly is scheduled to begin around 2025, Gateway Foundation representatives said.

This shining technological ring will feature amenities ranging from themed restaurants, viewing lounges, movie theaters and concert venues to bars, libraries, gyms, and a health spa.

Voyager will house 24 integrated habitation modules, each of which will be 65 feet long and 40 feet wide (20 by 12 meters). At near-lunar gravity, the rotating resort will have functional toilets, showers, and allow jogging and jumping in fun and novel ways.

But before the station can start spinning, its builders must establish the necessary orbital infrastructure and create smaller structures to test the concept.

Blincow explained during the Jan. 29 event that the current plan is to build the rotating space station in stages, beginning with a small-scale prototype station, in addition to a free-flying microgravity facility, both using Voyager components.

“This will be the next industrial revolution,” Blincow said.

Eventually, a Structure Truss Assembly Robot (STAR) will fabricate the frame of the Voyager and Gateway stations in orbit. Prior to that happening, however, a smaller, ground-based prototype, known as DSTAR, will test the technology here on Earth.

OAC’s truss assembly robot stands to be the first to build a space station in low Earth orbit and will serve as “the structural backbone of future projects in space,” OAC fabrication manager Tim Clements said during the event.

Currently, the machine is undergoing commissioning and shipping. It will then be completed and tested in California.

“The prototype will produce a truss section roughly 300 feet [90 m] in length in under 90 minutes,” Clements revealed during the live-streamed event. “DSTAR weighs almost 8 tons in mass, consisting of steel, electrical and mechanical components.”

OAC is also creating a robotic observer drone for remote viewing via a virtual reality headset as its first in-house development project.

“It’s going to be our eyes on the job site,” said Alatorre. “The observer drone operates in a support function. It can perch on existing craft. It can also be fully reusable and can fly and have a free-flight mode on extended missions.”

Long before Voyager Station can start accommodating guests, OAC needs to test both building a station in low Earth orbit and prove the viability of stable artificial gravity in space. The company plans to construct a prototype gravity ring that will measure 200 feet (61 m) in diameter and will be engineered to spin up to create artificial gravity near Mars’ level, which is about 40% that of Earth.

“The gravity ring is going to be a key technology demonstration project that we plan to build, assemble and operate in low Earth orbit in just a few years’ time,” said OAC co-founder Jeff Greenblatt. “The company also plans to use an orbital version of the DSTAR called the PSTAR, which stands for Prototype Structural Truss Assembly Robot.”

This gravity ring will act as a “near-term demonstrator,” which will take two to three years to build and launch. Once installed in orbit, its assembly will take just three days. This structure will act as the company’s test base for many of the technologies to be used to build Voyager Station.

“We haven’t seen an explosion of commercial activity in space,” Alatorre said. “The cost has been about $8,000 per kilogram [$17,600 per lb.] for a long time. But with the Falcon 9, you can do it for less than $2,000. And as Starship comes online, it will only cost a few hundred dollars.” (These were references to SpaceX launchers — the company’s workhorse Falcon 9 rocket and its Starship Mars vehicle, which is in development.)

“Microgravity is just brutal on our bodies,” Alatorre added “We need artificial gravity — a mechanism to give us a dosage of gravity to give us the ability to live long-term in space.”

The planned gravity ring may also become a research platform for international space agencies and private aerospace firms interested in the effects of partial artificial gravity on both non-living and living systems, OAC representatives said.

“This will give researchers an unprecedented opportunity to access that intermediate gravity regime,” Greenblatt said. “This will then pave the way for OAC to build larger, more complex structures in space, which is obviously necessary if we’re going to get to the point of building Voyager Station and other larger structures beyond.”

Looking into the future, government and private companies will be allowed to use the Voyager modules for lunar training missions and beyond, providing a launch pad for entrepreneurs to develop and market tourist activities in space.

“We don’t want the Voyager experience to be like being in an attack submarine in combat, so we’re [building] for comfort,” said Tom Spilker, OAC’s chief technology officer and vice president of engineering and space systems design. “It’s a bit smaller than the length of the U.S. Capitol building.”

“Despite the seemingly endless list of luxury amenities, there will also be airlocks for visitors,” Spilker added. “So anyone who can afford a space hotel can go on a private spacewalk, where the only thing between you and the universe is a faceplate.”

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Todd

Meet the swirlon, a new kind of matter that bends the laws of physics

Researchers discover a new state of active matter.

Fish school, insects swarm and birds fly in murmurations. Now, new research finds that on the most basic level, this kind of group behavior forms a new kind of active matter, called a swirlonic state.

Physical laws such as Newton’s second law of motion — which states that as a force applied to an object increases, its acceleration increases, and that as the object’s mass increases, its acceleration decreases — apply to passive, nonliving matter, ranging from atoms to planets. But much of the matter in the world is active matter and moves under its own, self-directed, force, said Nikolai Brilliantov, a mathematician at Skolkovo Institute of Science and Technology in Russia and the University of Leicester in England. Living things as diverse as bacteria, birds and humans can interact with the forces upon them. There are examples of non-living active matter, too. Nanoparticles known as “Janus particles,” are made up of two sides with different chemical properties. The interactions between the two sides create self-propelled movement.

To explore active matter, Brilliantov and his colleagues used a computer to simulate particles that could self-propel. These particles weren’t consciously interacting with the environment, Brilliantov told Live Science. Rather, they were more akin to simple bacteria or nanoparticles with internal sources of energy, but without information-processing abilities.

The first surprise was that this active matter behaves very differently than passive matter. Different states of passive matter can coexist, Brilliantov said. For example, a glass of liquid water can gradually evaporate into a gaseous state while still leaving liquid water behind. The active matter, by contrast, didn’t coexist in different phases; it was all solid, all liquid or all gas.

The particles also grouped together as large conglomerates, or quasi-particles, which milled together in a circular pattern around a central void, kind of like a swirl of schooling sardines. The researchers dubbed these particle conglomerates “swirlons,” and named the new state of matter they formed a “swirlonic state.”

In this swirlonic state, the particles displayed bizarre behavior. For example, they violated Newton’s second law: When a force was applied to them, they did not accelerate.

“[They] just move with a constant velocity, which is absolutely surprising,” Brilliantov said.

The simulations were basic, and experimental work with real-world active matter is an important next step, he said. Brilliantov and his colleagues also plan to do more complex simulations using active-matter particles with information-processing abilities. These will more closely resemble insects and animals and help to reveal the physical laws governing schooling, swarming and flocking. Ultimately the goal is to create self-assembling materials out of active matter, Brilliantov said, which makes it important to understand the phases of this kind of matter.

“It’s quite important that we see the nature of active matter” is much richer than that of passive matter, Brilliantov said.

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Newfound exoplanet could be ‘Rosetta Stone’ for studies of alien atmospheres

Gliese 486 b will probably get a lot of astronomical attention over the next few years.

Artist’s illustration of the newly discovered exoplanet Gliese 486 b, which lies just 26 light-years from Earth.

A newly discovered alien world could help astronomers better understand the atmospheres of rocky planets.

The newfound exoplanet, Gliese 486 b, circles a dim red dwarf star just 26 light-years from Earth and is about 1.3 times larger and 2.8 times more massive than our home planet, a new study reports.

Gliese 486 b whips around its host star once every 1.47 Earth days, and it crosses that star’s face from our perspective. Gliese 486 b is therefore the third-closest such “transiting” alien world known — and the closest one that orbits a red dwarf with a measured mass. (The star Gliese 486 is about 30% as massive as our sun.)

In addition, the discovery team determined that Gliese 486 b has a likely surface temperature of around 800 degrees Fahrenheit (430 degrees Celsius) — probably cool enough to support an atmosphere, and hot enough for that atmosphere to be studied from afar.

This combination “of physical and orbital characteristics of Gliese 486 b makes it the ‘Rosetta Stone’ for atmospheric investigations of rocky exoplanets,” study lead author Trifon Trifonov, of the Max Planck Institute for Astronomy in Heidelberg, Germany, told Space.com via email. (The Rosetta Stone, which was discovered in 1799, famously allowed archaeologists to translate Egyptian hieroglyphics for the first time.)

Trifonov and his colleagues spotted Gliese 486 b using the CARMENES spectrograph instrument, which is installed on the 3.5-meter telescope at the Calar Alto Observatory in Spain.

CARMENES finds planets via the “radial velocity” method, noticing slight wobbles in a star’s motion caused by the gravitational tug of an orbiting world. The instrument detected such a wobble with Gliese 486, one that recurs every 1.47 Earth days.

The team then studied Gliese 486 with NASA’s Transiting Exoplanet Survey Satellite (TESS). As its name suggests, TESS finds transiting worlds, flagging the tiny brightness dips they caused when crossing their host stars’ faces from the spacecraft’s perspective.

The newfound exoplanet Gliese 486 b orbits a red dwarf star about 30% as massive as Earth’s sun.

TESS saw a brightness dip with Gliese 486, and the 1.47-day timing matched, confirming the presence of an alien planet in the system. Trifonov and his team then characterized Gliese 486 b using the TESS and CARMENES data, as well as information from another spectrograph known as MAROON-X, which is on the 8.1-m Gemini North Telescope in Hawaii. (In case you were wondering, CARMENES and MAROON-X stand for “Calar Alto high-Resolution search for M dwarfs with Exo-earths with Near-infrared and optical Echelle spectrographs” and “M-dwarf Advanced Radial-velocity Observer of Neighboring Exoplanets,” respectively.)

For example, they determined the alien planet’s mass from the radial-velocity data and its size from the transit observations. Those two numbers, in turn, revealed Gliese 486 b’s density — about 7 grams per cubic centimeter (0.25 lbs. per cubic inch), which is in the same ballpark as Earth’s (5.5 grams per cubic centimeter, or 0.20 lbs. per cubic inch). The exoplanet therefore likely has an iron-silicate composition similar to that of Earth, the researchers wrote in the new study, which was published online today (March 4) in the journal Science.

The surface temperature, however, is closer to that of Venus, so Gliese 486 b is not a great candidate for life as we know it, said Trifonov, who envisions a world that’s “hot and dry, interspersed with volcanos and glowing lava rivers.”

Artist’s illustration of the surface of the newly discovered exoplanet Gliese 486 b. With a temperature of about 800 degrees Fahrenheit (430 degrees Celsius), Gliese 486 b possibly has an atmosphere.

In addition, because its orbit is so tight, Gliese 486 b is likely “tidally locked,” always showing the same face to its parent star, as the moon does to Earth. So the exoplanet may well have a blisteringly hot day side and a much colder night side — another possible impediment to life as we know it.

But there’s still ample reason to get excited about Gliese 486 b. For example, its proximity to Earth and other characteristics make it a great laboratory for learning about planetary atmospheres, Trifonov said.

“Future observations of Gliese 486 b will help us understand how well rocky planets can hold their atmospheres, what they are made of” and how they’re influenced by stellar radiation, he said.

The best candidate to make such observations is NASA’s $9.8 billion James Webb Space Telescope, which is scheduled to launch late this year.

“Soon after the JWST becomes operational, we may plan observations of Gliese 486 b,” Trifonov said. “Optimistically speaking, in about 2.5 to 3 years from now, we may know if the planet has an atmosphere or not, and, if yes, what is its composition.”

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Todd

First-ever ‘space hurricane’ detected over the North Pole

Any planet with plasma and a magnetic field could be victim to these ‘violent’ space storms, researchers said.

Artist’s concept of a space hurricane, pouring plasma high over the North Pole.

For the first time, astronomers have detected a powerful, 600-mile-wide (1,000 kilometers) hurricane of plasma in Earth’s upper atmosphere — a phenomenon they’re calling a “space hurricane.”

The space hurricane raged for nearly 8 hours on Aug. 20, 2014, swirling hundreds of miles above Earth’s magnetic North Pole, according to a study published Feb. 22 in the journal Nature Communications.

Made from a tangled mess of magnetic field lines and fast-flying solar wind, the hurricane was invisible to the naked eye — however, four weather satellites that passed over the North Pole detected a formation not unlike a typical terrestrial hurricane, the study authors wrote. The space hurricane was shaped like a funnel with a quiet “eye” at the center, surrounded by several counterclockwise-spinning spiral arms of plasma (ionized gas found all over the solar system, including in Earth’s atmosphere).

Instead of raining water, the space hurricane rained electrons directly into Earth’s upper atmosphere.

“Until now, it was uncertain that space plasma hurricanes even existed, so to prove this with such a striking observation is incredible,” study co-author Mike Lockwood, space scientist at the University of Reading in the U.K., said in a statement. “Tropical storms are associated with huge amounts of energy, and these space hurricanes must be created by unusually large and rapid transfer of solar wind energy and charged particles into the Earth’s upper atmosphere.”

Using a 3D model of the hurricane, the researchers hypothesized that the formation resulted from a complex interaction between incoming solar wind (high-speed gales of plasma periodically released by the sun) and the magnetic field over the North Pole.

While this is the first observed space hurricane, the researchers hypothesize that these “weather” systems could be common events on any planet with a magnetic shield and plasma in its atmosphere.

“Plasma and magnetic fields in the atmosphere of planets exist throughout the universe, so the findings suggest space hurricanes should be a widespread phenomena,” Lockwood said.

Should you fear the space hurricane? Probably not. The upper-atmosphere phenomenon poses little threat to our planet, the researchers noted, but it could impact existing space weather effects, for instance by increasing drag on satellites, or disrupting GPS and radio communications systems.

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Space photos: The most amazing images this week!

Rare atmospheric sprite and jet

Strange atmospheric phenomena can be seen on the right side of this image, photographed by the “cloud cam” at the Gemini North telescope on Maunakea in Hawaii. The red sprite and the blue jet seen here occurred in Earth’s upper atmosphere and were caused by electrical discharges. Sprites and jets are rarely witnessed from the ground, but they’re not uncommon above thunderstorms. The Gemini North telescope sits high above sea level at 13,800 feet (4,200 meters), offering a fantastic view of the phenomena.

A “black eye” galaxy

The Hubble Space Telescope snapped this image of the spiral galaxy NGC 4826, which can be found 17 million light-years away from Earth. The galaxy, which lies in the constellation of Coma Berenices (Berenice’s Hair), is often called the “black eye” galaxy because of the dark band of dust and gas sweeping across it, which you can see in this image.

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Space calendar 2021: Rocket launches, sky events, missions & more!

Here’s some, but click the link for lots more (and multiple uses of the word “conjunction”)

March

March 14: Daylight Saving Time begins. Turn your clocks forward one hour at 2 a.m. local time.

March 20: Vernal Equinox. Today at 5:37 a.m. EDT (0937 GMT) marks the first day of spring in the Northern Hemisphere and the first day of autumn in the Southern Hemisphere.

March 28: The full moon of March, known as the Full Worm Moon, arrives at 2:48 p.m. EDT (1817 GMT).

April

April 21-22: The Lyrid meteor shower, which is active April 16-30, peaks overnight.

April 26: The full moon of April, known as the Full Pink Moon, arrives at 11:32 p.m. EDT (0332 April 27 GMT). Because the moon will also be near perigee, or its closest point to Earth, this will also be a so-called “supermoon.”

May

May 4-5: The Eta Aquarid meteor shower, which is active from mid-April to the end of May, peaks overnight.

May 26: The full moon of May, known as the Full Flower Moon, arrives at 7:14 a.m. EDT (1114 GMT). It will also be the closest “supermoon” of the year. That night, a total lunar eclipse, also known as a “Blood Moon,” will be visible from Australia, parts of the western United States, western South America and Southeast Asia.

June

June 10: An annular solar eclipse, also known as a “ring of fire” eclipse, will be visible from parts of Russia, Greenland and and northern Canada. Skywatchers in Northern Asia, Europe and the United States will see a partial eclipse.

June 20: The solstice arrives at 11:16 p.m. EDT (0316 June 21 GMT), marking the first day of summer in the Northern Hemisphere and the first day of winter in the Southern Hemisphere.

June 24: The full moon of June, known as the Full Strawberry Moon, arrives at 2:40 p.m. EDT (1940 GMT).

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Black holes could be dark stars with ‘Planck hearts’

Black holes, those gravitational monsters so named because no light can escape their clutches, are by far the most mysterious objects in the universe.

But a new theory proposes that black holes may not be black at all. According to a new study, these black holes may instead be dark stars home to exotic physics at their core. This mysterious new physics may cause these dark stars to emit a strange type of radiation; that radiation could in turn explain all the mysterious dark matter in the universe, which tugs on everything but emits no light.

Dark stars
Thanks to Einstein’s theory of general relativity, which describes how matter warps space-time, we know that some massive stars can collapse in on themselves to such a degree that they just keep collapsing, shrinking down into an infinitely tiny point — a singularity.

Once the singularity forms, it surrounds itself with an event horizon. This is the ultimate one-way street in the universe. At the event horizon, the gravitational pull of the black hole is so strong that in order to leave, you’d have to travel faster than light does. Since traveling faster than the speed of light is utterly forbidden, anything that crosses the threshold is doomed forever.

Hence, a black hole.

These simple yet surprising statements have held up to decades of observations. Astronomers have watched as the atmosphere of a star gets sucked into a black hole. They’ve seen stars orbit black holes. Physicists on Earth have heard the gravitational waves emitted when black holes collide. We’ve even taken a picture of a black hole’s “shadow” — the hole it carves out from the glow of surrounding gas.

And yet, mysteries remain at the very heart of black hole science. The very property that defines a black hole — the singularity — seems to be physically impossible, because matter can’t actually collapse down to an infinitely tiny point.

Planck engines
That means the current understanding of black holes will eventually need to be updated or replaced with something else that can explain what’s at the center of a black hole.

But that doesn’t stop physicists from trying.

One theory of black hole singularities replaces those infinitely tiny points of infinitely compressed matter with something much more palatable: an incredibly tiny point of incredibly compressed matter. This is called a Planck core, because the idea theorizes that the matter inside a black hole is compressed all the way down to the smallest possible scale, the Planck length, which is 1.6 * 10^ minus 35 meters.

That’s … small.

With a Planck core, which wouldn’t be a singularity, a black hole would no longer host an event horizon — there would be no place where the gravitational pull exceeds the speed of light. But to outside observers, the gravitational pull would be so strong that it would look and act like an event horizon. Only extremely sensitive observations, which we do not yet have the technology for, would be able to tell the difference.

Dark matter
Radical problems require radical solutions, and so replacing “singularity” with “Planck core” isn’t all that far-fetched, even though the theory is barely more than a faint sketch of an outline, one without the physics or mathematics to confidently describe that kind of environment. In other words, Planck cores are the physics equivalent of spitballing ideas.

That’s a useful thing to do, because singularities need some serious out-of-the-box thinking. And there might be some bonus side-effects. Like, for example, explaining the mystery of dark matter.

Dark matter makes up 85% of the mass of the universe, and yet it never interacts with light. We can only determine its existence through its gravitational effects on normal, luminous matter. For example, we can watch stars orbit the centers of the galaxies, and use their orbital speeds to calculate the total amount of mass in those galaxies.

In a new paper, submitted Feb. 15 to the preprint database arXiv, physicist Igor Nikitin at the Fraunhofer Institute for Scientific Algorithms and Computing in Germany takes the “radical singularity” idea and kicks it up a notch. According to the paper, Planck cores may emit particles (because there’s no event horizon, these black holes aren’t completely black). Those particles could be familiar or something new.

Perhaps, they would be some form of particle that could explain dark matter. If black holes are really Planck stars, Nikitin wrote, and they are constantly emitting a stream of dark matter, they could explain the motions of stars within galaxies.

his idea probably won’t hold up to further scrutiny (there’s much more evidence for the existence of dark matter than just its effect on the motion of stars). But it’s a great example of how we need to come up with as many ideas as possible to explain black holes, because we never know what links there may be to other unsolved mysteries in the universe.

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Scientists find most distant quasar shooting powerful radio jets

An artistic visualization of the quasar P172+18

A newly discovered quasar from the early universe is the most distant found to date that’s shooting out powerful radio jets.

Astronomers using the European Southern Observatory’s (ESO) Very Large Telescope (VLT) recently discovered the quasar, called P172+18, which is so far away that it takes about 13 billion years for the light from this quasar to reach Earth, where we observe the object as it was when the universe was just 780 million years old. While the new find is not the most distant quasar ever detected, it appears to be the most distant radio-loud quasar, or radio jet-emitting quasar.

Quasars are extremely bright celestial objects powered by supermassive black holes that lie in the center of some galaxies; sometimes quasars are so bright that they eclipse the very galaxies containing them. Radio-loud quasars shoot out powerful jets that are strong sources of radio-wavelength emissions. This quasar was first identified as a radio source when scientists using the Magellan Telescope at Las Campanas Observatory in Chile detected these powerful jets.

“As soon as we got the data, we inspected it by eye, and we knew immediately that we had discovered the most distant radio-loud quasar known so far,” Eduardo Bañados of the Max Planck Institute for Astronomy in Germany, who led this discovery alongside ESO astronomer Chiara Mazzucchelli, said in a statement.

The distant, jet-shooting quasar is powered by a supermassive black hole that’s about 300 million times more massive than our sun and is growing quickly, pulling in and swallowing surrounding matter with its gravity.

“The black hole is eating up matter very rapidly, growing in mass at one of the highest rates ever observed,” Mazzucchelli said in the same statement.

The researchers think that there could be a connection between the quick growth of black holes like this and the jets that shoot out of radio-loud quasars like P172+18, according to the statement. In particular, the astronomers think that these powerful jets might interact with nearby gases in a way that pushes the gases into the gravitational grip of these black holes, increasing how much gas falls into them.

So, as they uncover more details about this quasar, scientists will also continue to learn about the supermassive black hole accompanying it far out in the universe.

“I find it very exciting to discover ‘new’ black holes for the first time, and to provide one more building block to understand the primordial Universe, where we come from, and ultimately ourselves,” Mazzucchelli said.

In addition to the VLT and the Magellan Telescope, which helped scientists to originally identify the radio signal that they now knows is a quasar, the team also used facilities including the National Radio Astronomy Observatory’s (NRAO) Very Large Array (VLA) in New Mexico and the Keck Telescope in Hawaii.

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All these artistic visualizations are actually just radio waves or graphs, right? They are not telescopes that you look through. So it is more like a wavemeter and something you look at rather than through, correct?

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I think you’re right, but then what do I know?
I look at the pretty pictures and pretend to understand in front of the smart kids.
I still get comments about the way I tie my shoelaces…
__________________________________________

Rare supernova relic found at the core of our Milky Way

NASA’s Chandra X-ray Observatory has discovered the remains of a rare kind of stellar explosion near the center of the Milky Way.

Supernovas are stellar explosions that seed the galaxy with elements vital for life. Sagittarius A East (or Sgr A East) is a supernova remnant that lies near Sagittarius A* — the supermassive black hole in the center of the Milky Way. This supernova remnant is the first known example in our own Milky Way galaxy of an unusual type of white dwarf stellar explosion called a Type Iax supernova, according to a statement from the Chandra X-ray Observatory.

“While we’ve found Type Iax supernovae in other galaxies, we haven’t identified evidence for one in the Milky Way until now,” Ping Zhou, lead author of the study from Nanjing University in China, said in the statement. “This discovery is important for getting a handle of the myriad ways white dwarfs explode.”

NASA’s Chandra X-ray Observatory captured a supernova remnant called Sagittarius A East (Sgr A East) near the center of our Milky Way galaxy.

There are different types of stellar explosions, ranging from those triggered by the collapse of massive stars, to those that are triggered by smaller white dwarf stars that have pulled too much material from a companion star or collided with another white dwarf.

White dwarf explosions — generally designated as Type Ia supernovas — are an important source of chromium, iron and nickel in the universe. However, using the Chandra observations, astronomers found Sgr A East produced different relative quantities of essential elements and created a less powerful explosion than a typical Type Ia supernova, suggesting it is instead a Type Iax supernova, according to the statement.

“This result shows us the diversity of types and causes of white dwarf explosions, and the different ways that they make these essential elements,” Shing-Chi Leung, co-author of the study from the California Institute of Technology, said in the statement. “If we’re right about the identity of this supernova’s remains, it would be the nearest known example to Earth.”

To explain the differences observed between these two types of supernovas, astronomers have suggested thermonuclear reactions, which trigger stellar explosions, move more slowly through white dwarf stars that result in Type Iax supernovas compared to Type Ia supernovas. Slower thermonuclear reactions would result in weaker explosions and, in turn, the release of different quantities of elements produced in the explosion. Part of the white dwarf may also be left behind during Type Iax supernovas, according to the statement.

In addition to the X-ray data from Chandra, astronomers used computer models to simulate slow-moving nuclear reactions in white dwarf stars. The computer models supported the Chandra observations of Sgr A East, suggesting it is a Type Iax supernova remnant.

“This supernova remnant is in the background of many Chandra images of our galaxy’s supermassive black hole taken over the last 20 years,” Zhiyuan Li, co-author of the study from Nanjing University, said in the statement. “We finally may have worked out what this object is and how it came to be.”

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Pictures from space! Our image of the day

Hydrogen in the Triangulum Galaxy

March 10, 2021: Stretching 1,500 light-years across, the ionized hydrogen in the Triangulum Galaxy shines bright in this image from the Hubble Space Telescope. The galaxy, more formally known as NGC 604, is a major area of star formation as this gas (most of which is hydrogen), collapses over time due to gravity, creating new stars.

March 9, 2021: This big, beautiful and blue galaxy is formally known as NGC 2336. In this image, captured by the Hubble Space Telescope, you can see the barred spiral galaxy, which lies about 100 million light-years away in the constellation Camelopardalis (the Giraffe), stretching across the cosmos, with a “wingspan” measuring about 200,000 light-years.

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Rocket wrote:

All these artistic visualizations are actually just radio waves or graphs, right? They are not telescopes that you look through. So it is more like a wavemeter and something you look at rather than through, correct?

Yes, most of this stuff we can’t actually see, it’s just data pulled down by instruments which they then give artistic impressions of. Most astronomy these days is done through instruments that detect gravity waves, radio waves, x-rays, microwaves, etc., and they just gives pings of intensity that you can then graph.

Visible light astronomy through traditional telescopes still happens, but I don’t think it’s where any of the cutting-edge science is happening. And even then, images they show you from visible-light telescopes are usually recoloured to emphasise what they want you to see, so you’re still not seeing what things really look like.

 

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Newfound super-Earth alien planet whips around its star every 0.67 days

Say hello to the extreme ‘super-Earth’ TOI-1685 b

NASA’s Transiting Exoplanet Survey Satellite is searching for planets outside our solar system, including those that could support life. The mission finds exoplanets that periodically block part of the light from their host stars — events called transits.

We keep getting reminders that the Milky Way’s planetary diversity dwarfs what we see in our own solar system.

The newfound exoplanet TOI-1685 b is yet another case in point. Astronomers found it circling a dim red dwarf star about 122 light-years from Earth. “Circling” is too ordinary a world for TOI-1685 b’s motion, however; the alien world whips around its parent star once every 0.67 Earth days.

Red dwarfs, also known as M dwarfs, are much smaller and dimmer than Earth’s sun, but TOI-1685 b’s extreme proximity to its host star, called TOI-1685, makes it a very toasty world nonetheless. The discovery team estimates its surface temperature to be around 1,465 degrees Fahrenheit (796 degrees Celsius).

The researchers, led by Paz Bluhm of Heidelberg University in Germany, first spotted TOI-1685 b in observations made by NASA’s Transiting Exoplanet Survey Satellite (TESS). As its name suggests, TESS looks for transits, the tiny brightness dips caused by planets crossing their host stars’ faces from the Earth-orbiting spacecraft’s perspective.

TESS noted such a dip around the red dwarf TOI-1685. Bluhm and her colleagues then confirmed the planet’s existence using data gathered by the CARMENES spectrograph instrument, which is installed on the 3.5-meter telescope at the Calar Alto Observatory in Spain. (CARMENES is short for “Calar Alto high-Resolution search for M dwarfs with Exo-earths with Near-infrared and optical Echelle spectrographs.)

CARMENES hunts for planets using the radial velocity, or Doppler, method — looking for little wobbles in a star’s motion caused by the gravitational tug of an orbiting planet.

The combined data allowed the team to determine that TOI-1685 b is a “super-Earth” about 1.7 times bigger, and 3.8 times more massive, than our home planet. The resulting bulk density — about 4.2 grams per cubic centimeter, or 0.15 lbs. per cubic inch — makes TOI-1685 b “the least dense ultra-short period planet around an M dwarf known to date,” Bluhm and her colleagues wrote in the discovery paper, which you can read for free on the online preprint site arXiv.org. (The paper has not yet been published in a peer-reviewed journal.)

For perspective: Earth’s bulk density is about 5.5 grams per cubic centimeter, or 0.20 lbs. per cubic inch.

The fact that TOI-1685 b transits and is quite warm makes it a good candidate for follow-up study by other instruments, the researchers wrote. In that regard, TOI-1685 b is similar to another recent exoplanet find made using TESS and CARMENES data, Gliese 486 b.

Bluhm and her team also saw another signal in the CARMENES TOI-1685 data, which could indicate a second planet in the system that orbits once every nine Earth days. If this candidate planet exists, it doesn’t transit, because TESS recorded no corresponding signal, the researchers wrote.

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Other planets in our Milky Way may have continents just like Earth

Scientists believe there may be planets in the Milky Way galaxy that have water and landmass properties similar to that of Earth.

A new study suggests that water may be present during a planet’s formation, with the researchers noting this was true for Earth, Mars and Venus. And because there’s nothing special about our solar system, the same conditions likely occurred as exoplanets in the galaxy formed.

“All our data [computer modeling] suggest that water was part of Earth’s building blocks, right from the beginning,” Anders Johansen, the lead author of the new research and an astronomer at the University of Copenhagen, said in a statement. “Because the water molecule is frequently occurring, there is a reasonable probability that it applies to all planets in the Milky Way. The decisive point for whether liquid water is present is the distance of the planet from its star.”

During the study, the researchers calculated how fast planets are formed. They found that tiny, millimeter-size particles of ice and carbon were the primary building blocks of Earth, along with pebbles that drift through the protoplanetary disc, an idea known as “pebble accretion.”

Early in its history, Earth grew by capturing pebbles that contained ice and carbon, until the planet reached about 1% of its current mass. For the next 5 million years, Earth continued to grow until it reached its current size, while the surface temperature continued to rise, resulting in the ice in the pebbles evaporating before reaching the planet’s surface, Johansen explained.

The researchers also found that the pebbles are comprised of between 10% and 35% ice for protoplanets, with smaller proportions for larger objects.

Some previous studies, such as one published in August 2019, have suggested that around 60% of Earth’s water comes from asteroid impacts.

With water found “everywhere” in the galaxy, according to Johansen the pebble accretion theory may give credence to the idea that other Milky Way planets formed in a similar manner to Earth, Mars and Venus and thus may be suitable for life.

“All planets in the Milky Way may be formed by the same building blocks, meaning that planets with the same amount of water and carbon as Earth — and thus potential places where life may be present — occur frequently around other stars in our galaxy, provided the temperature is right,” Johansen said.

One of the new study’s co-authors, University of Copenhagen professor Martin Bizzarro, also noted that not only do the planets in their model get the same amount of water, but they may sport continents as well, citing the theory that planets in the Milky Way had the same building blocks and temperatures. “It provides good opportunities for the emergence of life,” he said.

Next, Johansen and the researchers will utilize the spectroscopy features of future space telescopes, such as the James Webb Space Telescope, to determine exactly how much water vapor these planets have.

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Todd

This strange lava-rich alien planet is making itself a new atmosphere

The Hubble Space Telescope made the find

Scientists think they’ve spied an alien world that lost its atmosphere — then conjured itself a new one.

That’s according to a new analysis of Hubble Space Telescope observations gathered in 2017 of a planet dubbed GJ 1132 b. The world tightly orbits a red dwarf star located about 41 light-years from Earth, completing one circle every 1.5 Earth days and soaking up lots of stellar radiation in the process. And now, scientists think they see signs of a secondary atmosphere, one that was born of the exoplanet itself long after the planet formed.

“It’s super exciting because we believe the atmosphere that we see now was regenerated, so it could be a secondary atmosphere,” study co-author Raissa Estrela, an exoplanet scientist at NASA’s Jet Propulsion Laboratory (JPL) in California, said in a statement.

An artist’s depiction of the exoplanet GJ 1132 b, which orbits a red dwarf star about 41 light-years away from Earth and may sport lava continuously oozing up from cracks in its crust.

“We first thought that these highly irradiated planets could be pretty boring because we believed that they lost their atmospheres,” Estrela said. “But we looked at existing observations of this planet with Hubble and said, ‘Oh no, there is an atmosphere there.'”

An atmosphere is a tricky thing to hang onto. Earth’s is held fast to the planet, mostly by our magnetic field, but other worlds aren’t so lucky. Mars once had a thick atmosphere, for example, but most of it was stripped away after the planet lost its global magnetic field about 4 billion years ago.

Something similar can happen with exoplanets. Scientists think the result is sometimes dramatic, rapidly turning gassy planets smaller than Neptune into bare worlds.

This atmospheric loss can produce a planet about the same size as Earth, but one with a very different history than that of our home world. “How many terrestrial planets don’t begin as terrestrials?” Mark Swain, lead author of the new research and an exoplanet scientist at JPL, said in the same statement.

The researchers think that GJ 1132 b took things one step further. After the planet lost its hydrogen- and helium-rich basic atmosphere, it became a bare world. But the Hubble observations suggest that, today, GJ 1132 b is swathed in a mix of hydrogen, hydrogen cyanide, methane, and aerosol-rich haze that may resemble Earth’s smog.

To understand what’s happening in the system, the scientists are eyeing GJ 1132 b’s close relationship with its star, which tugs the world enough to keep the same side of the planet facing toward it at all times, mimicking how the moon orbits Earth.

An infographic compares the surface of GJ 1132 b with that of Earth and Saturn’s largest moon, Titan. Both GJ 1132 b and Titan offer strange parallels and stranger differences to Earth.

But because of the particulars of the planet’s orbit, the researchers suspect that in this case, the star pulls strongly enough on GJ 1132 b to dramatically heat the planet. The result could be a volcanically active world, the researchers concluded.

The strange atmosphere, then, could be born of gases leaching out of molten rock in the planet. In particular, the scientists paint a portrait of a molten world covered in a thin crust that may be cracked like an eggshell. Such cracks, created by the tug of the star on the planet, would allow gas to seep out, creating a second atmosphere.

The scientists hope that NASA’s powerful James Webb Space Telescope, currently scheduled to launch this fall, will be able to see the surface of GJ 1132 b in infrared light, which is tied to temperature.

“If there are magma pools or volcanism going on, those areas will be hotter,” Swain said. “That will generate more emission, and so they’ll be looking potentially at the actual geologic activity — which is exciting!”

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[Rocket]

Sean Robinson wrote:

I look at the pretty pictures and pretend to understand in front of the smart kids.

So what looks like an amazingly cool job looking at the most fabulous scenes is actually just listening to pings and looking at computer screens.

this link helped me understand what is going on with space photos.

https://wccftech.com/space-isnt-as-colorful-as-it-seems/

 

• This reply was modified 3 years, 10 months ago by Rocket.

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Rocket wrote:

So what looks like an amazingly cool job looking at the most fabulous scenes is actually just listening to pings and looking at computer screens

Basically yes:

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Todd, Sean Robinson, Rocket

Scorching-hot planet candidate spotted around famous star Vega

But the potential world still needs to be confirmed.

The bright star Vega as seen in two views from NASA’s Spitzer Space Telescope. Scientists have detected signs of scorching-hot a Neptune-sized exoplanet orbiting the star.

Astronomers have spotted a possible searing-hot planet orbiting Vega, one of the brightest and most famous stars in the sky.

The candidate alien planet, which still needs to be confirmed by follow-up observations or analyses, is roughly the size of Neptune and lies very close to Vega. It takes only 2.5 Earth days for the purported planet to make a single orbit around its sun.

Thanks to that proximity, the candidate planet’s surface temperature is probably around 5,390 degrees Fahrenheit (2,976 degrees Celsius), researchers calculated. That would make it the second-hottest planet known, if it does indeed exist. (The hottest, KELT-9b, is a whopping 7,800 degrees Fahrenheit, or 4,300 degrees C.)

Vega lies a mere 25 light-years from Earth and sits relatively high in the northern sky, so follow-up studies of this potential planetary system are a real possibility. Scientists will seek to confirm the Neptune-size world and also hunt for other possible planets around the famous star, which is in the constellation Lyra.

“This is a massive system, much larger than our own solar system,” Spencer Hurt, the lead author of a new study announcing the Vega candidate planet, said in a statement.

“There could be other planets throughout that system,” added Hurt, an undergraduate astronomy student at the University of Colorado, Boulder. “It’s just a matter of whether we can detect them.”

Team members spotted the candidate planet after looking at about 10 years of data collected by the Fred Lawrence Whipple Observatory in Arizona. They saw a slight wobble in the star’s motion, suggesting that an orbiting planet is tugging on it gravitationally.

Astronomers have been hunting for planets around Vega for many years. Back in 2013, astronomers announced evidence of a huge asteroid belt circling the star and expressed hope that the find may eventually lead the way to spotting planets. The discovery team added, however, that confirming planets may have to wait until after the launch of NASA’s powerful James Webb Space Telescope, which is scheduled to launch this October.

That said, Vega is so bright that professional telescopes can see the star in the sky even when it’s daylight, allowing for flexible observations. Hurt said he and his colleagues are hoping to find direct light emissions from the candidate planet in future studies, to confirm its existence.

Vegan planets and aliens are a staple of science fiction through the ages, ranging from Isaac Asimov’s “Foundation” series (which began in 1951) to the “Star Trek: The Original Series” episode “The Cage” (created in 1965 and first aired in 1988) to the movies or television shows “Spaceballs” (1987), “Contact” (1997) and “Babylon 5” (1993-98), among many others.

Vega’s appeal for science and science fiction is due in large part to its proximity to Earth. Twenty-five light-years is a small jaunt in cosmic terms, given that our Milky Way galaxy alone is roughly 100,000 light-years across. You can easily spot the star with the naked eye, and it rides high in the sky during the summer months of the northern hemisphere as part of the Summer Triangle asterism.

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Todd

The moon has a tail, and Earth wears it like a scarf once a month

The tail is invisible to the naked eye but appears on all-sky cameras during every new moon.

An animation showing how the moon’s sodium “tail” appears from Earth. Only a few days after each new moon, when the moon moves between Earth and the sun, is the tail visible from Earth.

Like a comet soaring through the cosmos, the moon is followed by a slender tail of irradiated matter — and Earth passes directly through it once a month.

According to a study published March 3 in the journal JGR Planets, the lunar tail is made of millions of sodium atoms blasted out of the lunar soil and into space by meteor strikes and then pushed hundreds of thousands of miles downstream by solar radiation. For a few days a month, when the new moon sits between Earth and the sun, our planet’s gravity drags that sodium tail into a long beam that wraps around Earth’s atmosphere before blasting into space on the opposite side.

The lunar tail is harmless and invisible to the naked eye. During those few new-moon days each month, however, the beam becomes visible to high-powered telescopes that can detect the faint orange glow of sodium in the sky. According to the study’s authors, the beam then appears as a fuzzy, glowing spot in the sky opposite the sun, about five times the diameter of the full moon and 50 times dimmer than human eyes can perceive.

Researchers first detected this “sodium spot” in the 1990s. But while the spot always appears at the same time in the lunar cycle, its brightness fluctuates wildly. To understand why, the authors of the new study used an all-sky camera (which can parse the faint wavelengths of light given off by specific elements, like sodium) to take some 21,000 images of the moon, from 2006 to 2019.

They noticed a few predictable patterns — for example, the spot appeared brighter when the moon’s orbit brought it closer to Earth — but also an unexpected one. Meteor data showed that the moon’s tail glowed more brightly during months when the rate of sporadic meteors (that is, meteors that aren’t part of a regular shower) was higher over Earth. When Earth gets pummeled by meteors, so does the moon. And sporadic meteor encounters had an even greater correlation with the moon spot’s brightness than recurring showers, such as the Leonid meteor shower, which peaks every November.

The reason for this? It may be that sporadic meteors have the potential to be faster, larger and more energetic than their counterparts in predictable showers, the study authors suggested. Meteors that slam into the moon with more force are more likely to blast large amounts of sodium higher into the atmosphere, the researchers said, creating a larger swarm of atoms for the sun’s photons (electromagnetic particles) to collide with and push toward Earth.

If a large enough asteroid crashed into the moon with enough force, it could even produce a sodium spot that anyone on Earth could see with the naked eye, James O’Donoghue, a planetary scientist at the Japan Aerospace Exploration Agency, told The New York Times. (O’Donoghue wasn’t involved in the research, but he did make the above lunar-tail animation for the research team.) In the meantime, we’ll have to be content with the knowledge that, once a month, our companion in the sky showers Earth with a pinch of cosmic pixie dust.

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A new approach to directly testing quantum gravity

Scientists have been trying to come up with a theory of quantum gravity for 100 years.

Abstract illustration of particles interacting at the quantum level.

It’s the ultimate dream of modern physics, to achieve what generations of scientists have failed to do for 100 years: concoct a quantum theory of gravity.

But any theory will have to face observational tests, and observational tests of quantum gravity are hard to come by, because of the incredible energies needed. But a team of physicists has proposed a clever solution: refine an age-old technique, and use it to probe the tiniest scales in the universe.

Putting a spin on it

Back in 1922, in the glory days of expanding our view of the quantum world, Otto Stern and Walther Gerlach reported an exciting new discovery that rocked the foundations of physics. It was a pretty simple setup: shoot some atoms with an overall electric charge (say, silver ions, but pretty much anything will do) down a tube. Surrounding the tube is a particular configuration of magnets so that the magnetic field in the tube isn’t perfectly even — it’s stronger on the bottom than it is on the top.

If we pretend for a moment that atoms are tiny little balls of spinning electric charge, then those spinning charges will interact with the magnetic field. Depending on the direction that their spins point in, the thin beam of atoms should spray out in all sorts of directions. This is basic electrodynamics.

But they don’t. Instead, the silver ions split into two uniform groups. One group is deflected up, and the other is deflected down. You could still think of atoms as tiny little balls of spinning electric charge, but that spin doesn’t point in any random direction. According to the Stern-Gerlach experiment, there are only two possible directions for the spin to point in: all the way up or all the way down.

This was the world’s introduction to quantum spin, which is now a cornerstone of our understanding of fundamental particles. It also altogether accelerated our understanding of the quantum world: Without a full quantum understanding of the subatomic world, you couldn’t explain the results of the Stern-Gerlach experiment.

Crossing path

And a full quantum understanding of the subatomic world is pretty bonkers. When you shoot the silver ions down the tube, they’re not exactly sure which spin they’re going to have — whether they will point up or down. Instead, in the language of quantum mechanics, they’re said to exist in a superposition of states until they’re observed (i.e., hit the wall at the end of the tube). The silver ions are both spin-up and spin-down, until they make a “choice” when the experiment is conducted.

It sounds crazy, but the math holds up. Using this language of superposition and probabilities, physicists are able to make predictions about how the subatomic world behaves.

Adding to the weirdness is the wave property of matter. It turns out that you can use the equations that govern wave motion to describe how those probabilities behave. In other words, the mathematics originally developed to figure out how ocean waves slosh back and forth was perfectly suited to describing how a subatomic particle would “decide” between being spin-up or spin-down.

No, it doesn’t make any sense. And yes, it totally works.

We can take advantage of this wave property of matter to explore the quantum world even more deeply. For example, waves can interfere with each other, either amplifying (like that horrible feedback sound when you bring a microphone too close to a speaker) or canceling each other out (like the noise-canceling headphones you use to get some much-needed shuteye on intercontinental flights).

I used sound waves in my examples, but you could just as easily interfere water waves, light wave — and matter waves.

Researchers in the 1960s realized that they could use a Stern-Gerlach setup to build a system where the quantum waves of spin could interfere with each other, allowing for ultra-precise measurements. But the setup was deemed impractical — you would need exceedingly exquisite control over the magnetic fields in order to make the setup work.

Into the quantum realm

But it’s not the 1960s anymore, and a team of physicists have been able to make quantum waves of spin interfere with each other, as detailed in a paper recently appearing on the preprint journal arXiv.

It works like this. First you take some atoms and super-cool them. This makes them easier to handle. Then you send them into an atom chip, which is an experimental device to trap and control the flow of atoms. You then subject them to a magnetic field, where the wave nature of their quantum spin comes out — the atoms are now in a superposition of spin states. You split the beam of atoms, so that different atoms follow different paths, then you recombine them.

Depending on how you tune the lengths of the two paths, you can get either constructive or destructive interference. Because we’re dealing with spins, either you get a whole lot of one spin or the other, or an even mix where everything washes out.

This setup lets you measure extremely tiny differences. If anything changes the length of the paths, or something messes with the spin nature of the atoms, then you can watch the resulting interference unfold.

The physicists haven’t conducted any experiments with this device yet — they’ve spent years just making the thing work. But now that it does work, they can investigate a variety of physical processes, and possibly open the door to quantum gravity.

We don’t have a fully quantum theory of gravity, which is needed to explain strong gravity at small scales. But this kind of spin interferometer can help us, because it’s an easy-to-build device that directly probes the quantum world. For example, you could place a massive object (relatively speaking) next to one of the paths, and use the interference result to measure the strength of gravity at extremely tiny scales. As another example, the spin interferometer could be used as a tiny gravitational wave detector (as ripples in space-time would alter the lengths of the paths), operating at much different frequencies than the current generation of detectors.

Whatever’s going on in the quantum world, the Stern-Gerlach experiment was one of the first to make it accessible. This device, developed almost a century later, could be the key to digging even deeper.

Read more: “Realization of a complete Stern-Gerlach interferometer: Towards a test of quantum gravity“

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Todd

Mars may hide oceans of water beneath its crust, study finds

Might not have been lost to space after all.

This mosaic of Mars is composed of about 100 Viking Orbiter images.

Oceans’ worth of water may remain buried in the crust of Mars, and not lost to space as previously long thought, a new study finds.

Prior work found Mars was once wet enough to cover its entire surface with an ocean of water about 330 to 4,920 feet (100 to 1,500 meters) deep, containing about half as much water as Earth’s Atlantic Ocean, NASA said in a statement. Since there is life virtually everywhere on Earth where there is water, this history of water on Mars raises the possibility that Mars was once home to life — and might host it still.

However, Mars is now cold and dry. Previously, scientists thought that after the Red Planet lost its protective magnetic field, solar radiation and the solar wind stripped it of much of its air and water. The amount of water Mars still possesses in its atmosphere and ice would only cover it with a global layer of water about 65 to 130 feet (20 to 40 m) thick.

But recent findings suggest Mars could not have lost all of its water to space. Data from NASA’s MAVEN (Mars Atmosphere and Volatile EvolutioN) mission and the European Space Agency’s Mars Express orbiter revealed that at the rate water disappears from the Red Planet’s atmosphere, Mars would have lost a global ocean of water only about 10 to 82 feet (3 to 25 m) deep over the course of 4.5 billion years.

Now scientists find that much of the water Mars once had may remain hidden in the crust of the Red Planet, locked away in the crystal structures of rocks beneath the Martian surface. They detailed their findings online March 16 in the journal Science and at the Lunar Planetary Science Conference.

Using data from rovers on and spacecraft orbiting Mars, as well as meteorites from Mars, the researchers developed a model of the Red Planet estimating how much water it started with and how much it might have lost over time. Potential mechanisms behind this loss included water escaping into space, as well as getting incorporated chemically into minerals.

One way scientists estimate how much water Mars lost to space involves analyzing hydrogen levels within its atmosphere and rocks. Every hydrogen atom contains one proton within its nucleus, but some possess an extra neutron, forming an isotope known as deuterium. Regular hydrogen escapes from a planet’s gravity more easily than heavier deuterium.

By comparing levels of lighter hydrogen and heavier deuterium atoms in Martian samples, researchers can estimate how much regular hydrogen the Red Planet might have lost over time. Since each water molecule is made of two hydrogen atoms and one oxygen atom, these estimates of Martian hydrogen loss therefore reflect how much Martian water has disappeared, as solar radiation broke water on Mars apart into hydrogen and oxygen molecules.

In the new study, the scientists found chemical reactions may have led between 30% to 99% of the water that Mars initially had to get locked into minerals and buried in the planet’s crust. Any remaining water was then lost to space, explaining the hydrogen-to-deuterium ratios seen on Mars.

All in all, the researchers suggested Mars lost 40% to 95% of its water during its Noachian period about 4.1 billion to 3.7 billion years ago. Their model suggested the amount of water on the Red Planet reached its current levels by about 3 billion years ago.

“Mars basically became the dry, arid planet we know today 3 billion years ago,” study lead author Eva Scheller, a planetary scientist at the California Institute of Technology in Pasadena, told Space.com.

The new estimates of the amount of water buried in the Martian crust range widely because of the uncertainty over the rate at which Mars lost water to space in the distant past, Scheller noted. She explained that NASA’s Perseverance rover, which landed on Mars in February, can help refine these estimates, “as it is going to one of the most ancient parts of the Martian crust, and so can help us nail down the past process of water loss to the crust much better.”

Although much of the water that Mars had may still be locked away within its crust, that does not mean any future astronauts to the Red Planet will find it easy to extract that water to help them live there, Scheller cautioned.

“All in all, there still isn’t a lot of water in the Martian crust, so you would have to heat a lot of rocks to get an appreciable amount of water,” Scheller said.

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What if Planet Nine is a baby black hole?

They may not be black or holes.

Some astronomers believe there is a massive planet, far beyond the orbit of Neptune, orbiting the sun — but after years of searching, scientists have not found this theoretical world, which they’ve dubbed “Planet Nine.”

This has spurred theorists to consider a radical hypothesis: Perhaps Planet Nine is not a planet but rather a small black hole that might be detectable from the theoretical radiation emitted from its edge, so-called Hawking radiation.

For centuries, astronomers have used variations in planetary orbits to predict the existence of new planets. When a planet’s orbit doesn’t quite line up with predictions based on everything else we know about the solar system, we need to update our physics (by, say, getting a better theory of gravity) or add more planets to the mix. For example, scientists’ inability to accurately describe Mercury’s orbit eventually led to Einstein’s theory of relativity. And, on the opposite end of the solar system, strange behaviors in the orbit of Uranus led to the discovery of Neptune.

In 2016, astronomers studied a collection of extremely distant objects in the solar system. Called trans-Neptunian objects (TNOs), these tiny, icy bodies are left over from the formation of the solar system, and they sit in a lonely, dark orbit beyond that of Neptune (hence the name).

A few of these TNOs have oddly clustered orbits that align with one another. The probability of that clustering happening by pure random chance is less than 1%, which led some astronomers to suspect that there might be a massive planet out there — something bigger than Neptune that orbits more than 10 times farther from the sun than Neptune does. They dubbed this hypothetical world Planet Nine. The gravity from such an object could draw these TNOs into clustered orbits, the idea goes.

The evidence for Planet Nine isn’t conclusive, though. The observations of TNOs may be biased, so astronomers may not have monitored a fair sample, meaning the odd clustering may be an artifact of our observation strategy rather than a real effect. For instance, researchers reported in February that the evidence for Planet Nine — particularly the clustering of TNOs — could be the result of where astronomers point their telescopes, Live Science reported. In other words, these TNOs only appear to be clustering because of our “biased” observations.

Plus, there’s the glaring reality that, after almost five years of searching, nobody has found Planet Nine.

A dark motivation

If Planet Nine is indeed out there, it may be on a part of its orbit that takes it so far away from the sun that we can’t observe it with current technology. But even our deepest, most sensitive scans have turned up nothing.

So now, astronomers have proposed an alternative hypothesis: Maybe Planet Nine isn’t a planet at all but rather a small black hole.

Small black holes (and “small,” here means planet-size) are very interesting to astronomers. All black holes we know of in the universe come from the deaths of massive stars. And because only the most massive stars (no smaller than, say, 10 solar masses) are big enough to form a black hole, they can only leave behind black holes with a minimum mass of around 5 times that of the sun.

But black holes smaller than that could have formed in the extreme conditions of the early universe. These primordial black holes could flood the cosmos. But cosmological observations have ruled out most models of primordial black hole formation, with a few narrow exceptions — like planet-size black holes.

So, if scientists can confirm that a small black hole is orbiting the sun, it could provide an intriguing look at one of the greatest mysteries of modern cosmology.

A perilous journey

In the 1970s, famed physicist Stephen Hawking theorized that black holes aren’t exactly 100% black. Due to a complex interaction between gravity and quantum forces at the event horizon, or boundary of a black hole, he proposed, black holes can indeed feebly emit radiation, slowly shrinking in the process.

And when I say “feebly,” I really mean it: A black hole the mass of the sun would emit a single photon — yes, one electromagnetic particle — every year. That’s hopelessly undetectable.

But a small, nearby black hole (like, say, Planet Nine) might be more accessible. Previous research had already shown that its Hawking radiation would be too weak to be seen from Earth, but new research, published in January in the preprint database arXiv, investigated if a flyby mission would have a better chance of spotting the Hawking radiation from such a black hole..

Alas, even using a fleet of lightweight, fast spacecraft to scour the outer system, we are very unlikely to spot Planet Nine through its Hawking radiation. The radiation is just too weak, and because we don’t know the location of the black hole, we can’t guarantee we can get close enough in a chance flyby.

But not all hope is lost. If scientists canmore conclusively pin down the location of the hypothetical Planet Nine using other observations and it turns out to be a black hole, then a targeted mission can fly close to its event horizon and possibly orbit it.

There, we would have direct observational access to one of the most extreme gravitational environments in the universe. No wonder astronomers are excited by the prospect of a black hole in our solar backyard. A mission there would be incredibly expensive and time-consuming. But we have experience with these kinds of long-distance missions in the form of New Horizons, the NASA probe that is currently sailing through the Kuiper belt. It’s within our technological reach to design and fly a longer-term version of New Horizons to visit a nearby black hole.

And it would be totally worth it.

Black holes are perhaps the most mysterious objects in the cosmos, and we do not fully understand them. In particular, Hawking radiation itself would teach us about the relationship between gravity and quantum mechanics at small scales. If Planet 9 is a black hole (and that’s a big “if” indeed), within a few years we could launch a mission to observe it in detail, and hopefully answer some long-burning questions in physics.

We would have a window into brand-new physics, and it would just be sitting there, waiting for us to look through it.

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Todd

Mars long ago was wet. You may be surprised where the water went

WASHINGTON (Reuters) – Mars was once a wet world, with abundant bodies of water on its surface. But this changed dramatically billions of years ago, leaving behind the desolate landscape known today. So what happened to the water? Scientists have a new hypothesis.

Researchers said this week that somewhere between about 30% and 99% of it may now be trapped within minerals in the Martian crust, running counter to the long-held notion that it simply was lost into space by escaping through the upper atmosphere.

“We find the majority of Mars’ water was lost to the crust. The water was lost by 3 billion years ago, meaning Mars has been the dry planet it is today for the past 3 billion years,” said California Institute of Technology PhD candidate Eva Scheller, lead author of the NASA-funded study published on Tuesday in the journal Science.

Early in its history, Mars may have possessed liquid water on its surface approximately equivalent in volume to half of the Atlantic Ocean, enough to have covered the entire planet with water perhaps up to nearly a mile (1.5 km) deep.

Water is made up of one oxygen and two hydrogen atoms. The amount of a hydrogen isotope, or variant, called deuterium present on Mars provided some clues about the water loss. Unlike most hydrogen atoms that have just a single proton within the atomic nucleus, deuterium – or “heavy” hydrogen – boasts a proton and a neutron.

Ordinary hydrogen can escape through the atmosphere into space more readily than deuterium. Water loss through the atmosphere, according to scientists, would leave behind a very large ratio of deuterium compared to ordinary hydrogen. The researchers used a model that simulated the hydrogen isotope composition and water volume of Mars.

“There are three key processes within this model: water input from volcanism, water loss to space and water loss to the crust. Through this model and matching it to our hydrogen isotope data set, we can calculate how much water was lost to space and to crust,” Scheller said.

The researchers suggested that a lot of the water did not actually leave the planet, but rather ended up trapped in various minerals that contain water as part of their mineral structure – clays and sulfates in particular.

This trapped water, while apparently plentiful when taken as a whole, may not provide a practical resource for future astronaut missions to Mars.

“The amount of water within a rock or mineral is very small. You would have to heat a lot of rock to release water in an appreciable amount,” Scheller said.

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Sean Robinson, Todd

This jet from a monster black hole is so huge it dwarfs our Milky Way galaxy

Astronomers have spotted a distant jet-shooting supermasive black hole known as PJ352-15 for short

A space telescope spotted a distant supermassive black hole spurting an X-ray jet.

Astronomers using NASA’s Chandra X-ray Observatory found the jet coming from an object roughly 12.7 billion light-years from Earth, which is pretty early in the universe’s 13.77-billion-year-old history. If confirmed, this would be one of the farthest jet-shooting objects of its kind yet known.

The jet comes from an object known as a quasar, which are active galactic nuclei that feed off of supermassive black holes and can emit extraordinary amounts of energy. Astronomers hope that by studying the jet, called PSO J352.4034-15.3373 (PJ352-15 for short), they can learn how huge black holes came together so early in the universe’s history.

“Despite their powerful gravity and fearsome reputation, black holes do not inevitably pull in everything that approaches close to them,” NASA explained in a statement March 9.

“Material orbiting around a black hole in a disk needs to lose speed and energy before it can fall farther inwards to cross the so-called event horizon, the point of no return. Magnetic fields can cause a braking effect on the disk as they power a jet, which is one key way for material in the disk to lose energy and, therefore, enhance the rate of growth of black holes,” the statement continued.

Astronomers peered at PJ325-15 for three days using Chandra, which is optimized for X-ray observations. The jet stretches about 1.5 times as long as the Milky Way, measuring a distance of roughly 160,000 light-years away from the quasar. (The Milky Way is roughly 100,000 light-years across.)

The jet far surpasses the longest one ever spotted from the first billion years after the Big Bang that formed the universe which was a relative squeaker at only 5,000 light-years in length, NASA said. PJ325-15 is also roughly 300 million light-years further from Earth than any jet ever before spotted.

“The length of this jet is significant because it means that the supermassive black hole powering it has been growing for a considerable period of time,” said study co-author Eduardo Bañados, a staff astronomer at the Max Planck Institute for Astronomy in Germany, in the same statement.

“Around supermassive black holes,” stated study leader Thomas Connor, a NASA postdoctoral fellow at NASA’s Jet Propulsion Laboratory in California, “we think jets can take enough energy away so material can fall inward and the black hole can grow.”

A paper based on the research is available on the preprint website Arxiv and has also been accepted for publication in The Astrophysical Journal.

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Todd

Pictures from space! Our image of the day

Outflows from infant stars

March 18, 2021: Researchers using previously collected data from the Hubble and Spitzer space telescopes and the ESA’s Herschel Space Telescope to study 304 developing stars in the Orion Complex, which is the closest star-forming region to Earth. In this new study, they looked at the star-forming process as, when hydrogen clouds collapse into new stars, there is a ton of leftover gas. Previously, scientists thought that the hot gas leaves young stars in outflowing jets and intense winds which stops its growth, but this new study finds fault in this explanation.

The Emerald Isle

March 17, 2021: The Emerald Isle, otherwise known as Ireland, is seen here from space, imaged by NASA’s Aqua satellite. The image, shared by NASA’s History Office on Twitter for St. Patrick’s Day, shows the nation’s signature feature, visible all the way from space: the lush and rolling green hills that cover the Island which lies in the North Atlantic just to the west of Great Britain.

Faint threads

March 16, 2021: Hubble spotted this lenticular galaxy, a cross between a spiral and elliptical-shaped galaxy, known as NGC 1947. The galaxy, which was originally discovered over 200 years ago, can only be viewed from the southern hemisphere and can be found in the Dorado (Dolphinfish) constellation about 40 million light-years away from Earth.

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Rocket, Todd

A supermassive black hole is speeding through space, and astronomers don’t know why

The supermassive black hole could be being dragged along by an invisible partner.

A supermassive black hole is racing across the universe at 110,000 mph (177,000 km/h), and the astronomers who spotted it don’t know why.

The fast-moving black hole, which is roughly 3 million times heavier than our sun, is zipping through the center of the galaxy J0437+2456, about 230 million light-years away.

Scientists have long theorized that black holes could move, but such movement is rare because their giant mass requires an equally enormous force to get them going.

“We don’t expect the majority of supermassive black holes to be moving; they’re usually content to just sit around,” Dominic Pesce, study leader and astronomer at the Harvard and Smithsonian Center for Astrophysics, said in a statement.

To begin their search for this infrequent cosmic occurrence, the researchers compared the velocities of 10 supermassive black holes with the galaxies they formed the centre of , focusing on the black holes with water inside their accretion disks — the spiral-shaped collections of cosmic material in orbit around the black holes.

Why water? As water orbits a black hole, it collides with other material, and the electrons surrounding the hydrogen and oxygen atoms that make up water molecules get excited to higher energy levels. When these electrons return to their ground state, they emit a beam of laser-like microwave radiation called a maser.

By taking advantage of a cosmic phenomenon known as red-shift, in which objects moving away have their light stretched to longer (and therefore redder) wavelengths, the astronomers were able to observe the extent to which the maser light from the accretion disk was shifted away from its known frequency when stationary, and thereby gauge the speed of the moving black hole.

They took more observations from various telescopes and combined them all together using a technique called very long baseline interferometry (VLBI); with this technique, the researchers could combine the images from several telescopes to effectively act like an image captured by a very big telescope, about the size of the distance between them. In that way, the scientists could precisely measure the velocity of the black holes it had originated from.

One of the telescopes the researchers used for the experiment was the Arecibo Observatory, which has since been decommissioned after the instrument platform crashed into the telescope’s disk in December 2020.

Of the 10 black holes they measured, nine were at rest, and one was on the move. Though 110,000 mph (177,000 km/h) is pretty fast, it’s not the fastest supermassive black hole. Scientists previously clocked a supermassive black hole hurtling through space at 5 million mph (7.2 million km/h), they reported in 2017 in the journal Astronomy & Astrophysics.

The researchers don’t know what could have made such a heavy object move at such a high speed, but they came up with two possibilities.

“We may be observing the aftermath of two supermassive black holes merging,” Jim Condon, a radio astronomer at the National Radio Astronomy Observatory, said in a statement. “The result of such a merger can cause the newborn black hole to recoil, and we may be watching it in the act of recoiling or as it settles down again.”

The other possibility is considered by astronomers to be much rarer and more novel: The supermassive black hole may be part of a pair with another black hole that’s invisible to their measurements.

“Despite every expectation that they really ought to be out there in some abundance, scientists have had a hard time identifying clear examples of binary supermassive black holes,” Pesce said. “What we could be seeing in the galaxy J0437+2456 is one of the black holes in such a pair, with the other remaining hidden to our radio observations because of its lack of maser emission.”

If the black hole is being tugged around by an even bigger, invisible one, this could explain why it’s traveling so fast, but more observations will be needed to get to the bottom of the mystery.

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Rocket, Todd

Interstellar object ‘Oumuamua is a pancake-shaped chunk of a Pluto-like planet

The strange tale of our first interstellar visitor keeps getting weirder.

The first known visitor from interstellar space, ‘Oumuamua, was likely a pancake-shaped chip off a Pluto-like world, researchers say.

These findings may shed light on the stuff a new class of planet, an exo-Pluto, is made of, scientists added.

Astronomers first detected the mysterious visitor named 1I/’Oumuamua — meaning ‘scout’ or ‘messenger’ in Hawaiian — in 2017. ‘Oumuamua’s speed and trajectory revealed it originated outside the solar system, making it the first known interstellar object.

The second known interstellar object, 2I/Borisov, was detected in 2019. Borisov was very clearly a comet, spewing out gases and possessing a composition much like comets long seen in the solar system.

An interstellar comet? Asteroid? Something else?

An artist’s concept of the ‘Oumuamua interstellar object as a pancake-shaped disk. A new study suggests it was once part of a Pluto-like exoplanet.

In a number of key ways, ‘Oumuamua resembled a comet. For example, scientists could not explain its movements through space by the force of gravity alone. This suggested ‘Oumuamua was jetting out gas from its sunlit side that was pushing it like a rocket, study co-author Steven Desch, an astrophysicist and planetary scientist at Arizona State University in Tempe, told Space.com.

However, if ‘Oumuamua was a comet, it was unlike any previously seen in the solar system. It lacked any detectable escaping gas, unlike the big tails typically spotted streaming from comets. In addition, its shape — resembling either a cigar or a pancake — was unlike any known comet. Moreover, the rocket-like push seen from ‘Oumuamua was stronger than what researchers expected from comets.

All these bizarre features ‘Oumuamua’s even led some researchers to speculate that it had alien origins.

“Everybody is interested in aliens, and it was inevitable that this first object outside the solar system would make people think of aliens,” Desch said in a statement. “But it’s important in science not to jump to conclusions.”

Now scientists find ‘Oumuamua might not be a piece of alien technology, but a chip off a Pluto-like world.

A strange new object

Researchers speculated that ‘Oumuamua was not made largely of water ice like known comets, but perhaps of other kinds of ices. They calculated how quickly such ices would sublimate — convert from a solid directly to a gas — as ‘Oumuamua flew by the sun, and the rocket-like push it would get from these escaping gases.

The scientists also noted some ices are far more reflective than often assumed. If ‘Oumuamua was made from these shiny ices, it might be smaller than previously estimated based on the light that astronomers detected from it. A tinier size for the interstellar visitor would mean any push from sublimating gases would have a larger effect than usually seen with comets, helping explain the unexpected speed with which it zipped away from the sun.

The researchers found one ice in particular — solid nitrogen — could explain all of ‘Oumuamua’s features and behavior. Solid nitrogen ice is seen on the surface of Pluto and Triton, suggesting this interstellar visitor could be made from the same material. “It was very satisfying to refine our calculations and see everything fall into place,” Desch said.

Any nitrogen gas escaping from ‘Oumuamua would have proven very difficult for astronomers to detect with the telescopes used to monitor it. “In essence, there was a tail like one would expect for a comet, it is just that because of what it is made of, we didn’t detect it,” study co-author Alan Jackson, an astrophysicist and planetary scientist at Arizona State University in Tempe, told Space.com.

An interstellar flapjack

An artist’s illustration of the evolution of the interstellar object ‘Oumuamua, whose weird, elongated shape may have come from tidal forces.

These new findings suggest ‘Oumuamua was shaped more like a pancake than a cigar. It may also be smaller than previously thought — just 147 by 144 by 24 feet (45 by 44 by 7.5 meters) in size when astronomers first detected it. In comparison, prior estimates suggested ‘Oumuamua was about 1,300 feet (400 m) long.

The researchers suggested that ‘Oumuamua likely wasn’t flat when it first entered the solar system. However, the light from the sun ultimately eroded it to a sliver, wearing away more than 95% of its mass.

“The same thing should happen with water-ice comets, but at a much smaller level,” Jackson said. Water ice sublimates much slower than nitrogen ice, Desch explained. In addition, Jackson noted ‘Oumuamua may have stayed together as one piece as it sublimated because it was made all of the same material — in contrast, most comets in the solar system are mixtures of rock, water ice and other ingredients, “so they tend to evaporate unevenly. This is partly why comets often break up when they pass very close to the sun.”

These findings suggest interstellar objects such as ‘Oumuamua may give us our first view of a hitherto unknown type of planet — an exo-Pluto. All in all, ‘Oumuamua may be the first known sample of an exoplanet brought into the solar system, the researchers said.

“The thought that what we saw could be a chunk of an actual exoplanet is thrilling,” Desch said.

Piece of an exo-Pluto

Based on ‘Oumuamua’s speed and trajectory, the researchers suggested this fragment of nearly pure nitrogen ice was slung away from a young star system about 400 million to 500 million years ago, possibly from the Perseus arm of the Milky Way. When it comes to what to call this potentially new class of objects, Desch suggested exo-Pluto fragments or Pluto-like fragments, whereas Jackson suggested nitrogen-ice comets.

The scientists calculated the rate at which cosmic impacts would have knocked chunks of ice off the surfaces of Pluto and similar bodies over the course of the solar system’s history. They estimated such collisions might have generated 100 trillion fragments, about half of which are water ice and the other half nitrogen ice. All in all, “about 1 in 1,000 comets in our solar system must be objects like ‘Oumuamua,” Desch said. One such example may be the comet C/2016 R2, discovered in 2016, he noted.

The researchers also calculated the chances that a nitrogen-ice comet from another star would reach our solar system. Their findings suggested “the outer reaches of a lot of planetary systems look very much like our own,” Jackson said. “It is difficult to get information about the outer reaches of exoplanetary systems with the methods that we usually use to look for planets, so this gives us a unique way to get a sense of what exoplanetary systems are like.”

Future telescopes such as the Vera Rubin Observatory in Chile could help regularly scan huge swaths of the sky and detect even more interstellar objects to learn more about them. In addition, “there has also been some work on concepts for space missions that could intercept a future object like ‘Oumuamua,” Jackson said. “That to me is an incredibly exciting prospect — an up close look at something that originated from outside our solar system.”

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Rocket, Todd

First image of a black hole gets a polarizing update that sheds light on magnetic fields

Following the release of the first image of a black hole in 2019, astronomers have captured a new polarized view of the black hole.

Following the mind-boggling release of the first image ever captured of a black hole, astronomers have done it again, revealing a new view of the massive celestial object and shedding light on how magnetic fields behave close to black holes.

In 2019, the Event Horizon Telescope (EHT) collaboration produced the first-ever image of a black hole, which lies at the center of the M87 galaxy 55 million light-years from Earth. The image showed a bright ring with a dark center, which is the black hole’s shadow. In capturing this image, astronomers noticed a significant amount of polarized light around the black hole. Now, the collaboration has revealed a new look at the black hole, showing what it looks like in polarized light.

Polarized light waves have a different orientation and brightness compared with unpolarized light. And, just like how light is polarized when it passes through some sunglasses, light is polarized when it’s emitted in magnetized and hot areas of space.

As polarization is a signature of magnetic fields, this image makes it clear that the black hole’s ring is magnetized. This polarized view “tells us that the emission in the ring is most certainly produced by magnetic fields that are located very close to the event horizon,” Monika Moscibrodzka, coordinator of the EHT Polarimetry Working Group and assistant professor at Radboud Universiteit in the Netherlands, told Space.com.

This is the first time that astronomers have been able to measure polarization so close to the edge of a black hole. Not only is this new view of this black hole spectacular to look at, but the image is revealing new information about the powerful radio jets shooting from M87.

“In the first images, we showed intensity only,” Moscibrodzka said about the first-released image of the object. “Now, we add polarization information on the top of that original image.”

“The new polarized images mark important steps towards learning more about the gas near the black hole, and in turn how black holes grow and launch jets,” Jason Dexter, Assistant Professor at the University of Colorado Boulder and coordinator of the EHT Theory Working Group, told Space.com in an email.

To capture the black hole, the collaboration used eight telescopes from around the world, combining their power to create a virtual Earth-sized telescope (the EHT).

“The radio telescopes of the EHT have receivers that record the sky signal in polarized light,” Ivan Marti-Vidal, also a coordinator of the EHT Polarimetry Working Group and GenT Distinguished Researcher at the Universitat de Valencia in Spain, told Space.com. “These polarized receivers work in a way similar to that of the polarized sunglasses that some people use.”

By showing the black hole in M87 through polarized light, the team got a better look at the object’s event horizon, which is also known as the “point of no return” because it’s the point at which no matter can get closer to the black hole without being pulled in. They also were able to better study the interaction with the object’s accretion disk, which is a disk of hot gas and other diffuse material that falls in toward a black hole and swirls around it.

The team’s observations and this new view of the object in M87 is deepening scientists’ understanding of the structure of magnetic fields just outside of a black hole, as it has remained a mystery how jets larger than the galaxy itself are emitted from the black hole at its heart.

“Astronomers have long thought that magnetic fields carried by the hot gas near black holes play an important role in letting the gas fall in, and in launching relativistic jets of energetic particles out into the surrounding galaxy. The polarized image we see tells us about the structure and strength of these magnetic fields very close to the black hole in M87, where the jet is launched,” Dexter said.

This image shows the jet in the M87 galaxy in polarized light, as captured by ALMA. This image reveals the structure of the magnetic field along the jet.

But these observations didn’t just reveal magnetic fields on the edge of the black hole in M87, they also show that the gas there is very strongly magnetized.

“The main finding is that we not only see the magnetic fields near the black hole as expected, but they also appear to be strong. Our results indicate that the magnetic fields can push the gas around and resist being stretched. The result is an interesting clue to how black holes feed on gas and grow,” Dexter added.

“We still don’t know all the details of how jets are generated, but we know that magnetic fields may play a critical role,” Marti-Vidal said. Going forward, the team hopes to continue observing M87, they told Space.com, not just in polarization but also “at different wavelengths [of light], to build a more complete picture of the black hole’s surroundings and probe [the] magnetic fields in more detail,” they added.

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Rocket, Todd

To be declassified: UFO broke sound barrier with no sonic boom

In a Fox News interview, Trump’s former intelligence director said the sightings are difficult to explain.

A previously declassified video of an alleged UFO sighting from the U.S. Navy.

More inexplicable sightings of unidentified flying objects (UFOs) will be released for public scrutiny in June — including a UFO that broke the sound barrier without producing a sonic boom.

Speaking on Fox News, the former director of National Intelligence, John Ratcliffe, said Saturday (March 20) that the sightings are “difficult to explain.” Ratcliffe, who served in the Trump administration, said he’d hoped to declassify the reports during his tenure but that they will be released by the Pentagon by June 1.

It’s not the first time the military has released strange reports, and even videos, of UFOs, known in military parlance as unidentified aerial phenomena (UAPs). In April 2020, the U.S. Navy released three videos appearing to show aircraft flying faster than the speed of sound. And Senate intelligence reports reveal that the Pentagon is still on the hunt for UFOs or UAPs. But check your excitement, Fox Mulder — the military is generally more concerned about whether UAPs might be secret aircraft or weapons developed by other nations than it is about finding evidence of ET in our midst.

According to Newsweek, Ratcliffe said the upcoming Pentagon report will include more sightings and reports of objects moving in seemingly impossible ways or breaking the speed of sound without an accompanying sonic boom. The unexplained sightings occurred all over the world, he said, and include events picked up on automated sensors and not just by human eyes.

“There are instances where we don’t have good explanations for some of the things that we’ve seen,” Ratcliffe told Fox News.

The report and declassification is required under the Intelligence Authorization Act for 2021.

However, the sightings may not even represent advanced Earth technology. Debunkers have suggested that the apparent extreme speed of the aircraft in the videos released in April 2020 could be an optical illusion called parallax. This effect occurs when an object close to a camera lens appears to be moving, sometimes quite quickly, as the camera moves, just because it’s closer to the lens than objects in the background. (A video example is available at SyfyWire.) Thus, the objects in the video could be as mundane as passenger planes or weather balloons. Some of the sudden movements in the videos may be artifacts of the camera zooming or sharpening the image, Vice reported.

There are also declassified experimental aircraft that can do things like break the speed of sound without the enormous “crack” of a sonic boom. NASA’s X-59 Quiet SuperSonic Technology aircraft, which is under construction and not yet in flight, is designed to fly faster than sound without making more than a gentle thump to listeners on the ground. It’s unknown if governments have similar, secret technology in testing or use.

Whatever the to-be-released videos show, it’s a time of unprecedented document release around UFOs. In January, the CIA unveiled three decades’ worth of documents about mysterious incidents reported to or investigated by the agency.

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Todd

Stunning Hubble image shows a big galaxy full of blue stars

NASA’s statement calls NGC 2336 “the quintessential galaxy.”

The Hubble Space Telescope captured an image of the brilliant, blue galaxy NGC 2336.

Imagine a galaxy and what comes to mind likely looks like NGC 2336, a shimmering swirl of stars.

And just days before a software glitch temporarily shut down the Hubble Space Telescope, the iconic spacecraft sent home a stunning image of the big, beautiful, and brilliantly blue galaxy. NASA uploaded the image of NGC 2336, a galaxy located about 100 million light-years from Earth in the constellation of Camelopardalis (aka the Giraffe), on Friday, March 5, two days before the telescope unexpectedly shut down. (The telescope has since resumed operations.)

In a statement about the new image, NASA calls NGC 2336 “the quintessential galaxy.” NGC 2336 is a barred spiral galaxy, meaning it has a star-dense center in the shape of a bar, with arms that spiral out from the ends of the bar. The galaxy is also very large, 200,000 light-years across according to the NASA statement.

This is far from the largest galaxy to be discovered, the honor of which goes to IC 1101, which is 50 times the size of our Milky Way at 5.5 million light-years across. Still, it’s on the large end of most spiral galaxies, which can measure between about 16,000 light-years and 300,000 light-years across.

The bright blue stars twinkling throughout NGC 2336’s spiral arms make the galaxy especially beautiful. These are young stars, which give off bright, blue light. At NGC 2336’s center is a darker, redder area comprised mostly of older stars.

German astronomer Wilhelm Tempel discovered this “quintessential galaxy” in 1876 using a much smaller telescope than Hubble, with a mirror about one-tenth the size of Hubble’s.

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Todd

A ‘lump’ of dark matter may be ripping apart Taurus’ face

Stars are ‘dissolving’ in the bull’s head, researchers say

The Hyades — a young, V-shaped cluster of stars swooshing through the head of the constellation Taurus — is slowly being ripped apart by an enormous, invisible mass, a new study suggests. This unrest in the bull’s head could point to an ancient cache of dark matter left over from the Milky Way’s creation, the study authors said.

In the new paper, published March 24 in the journal Astronomy and Astrophysics, researchers used data from the European Space Agency’s (ESA) Gaia star-mapping satellite to investigate the history of the Hyades. Located about 150 light-years from Earth, this family of several hundred stars is the closest star cluster to our solar system, and it’s clearly visible in the night sky. (One of its brighter stars, Epsilon Tauri, is also called the “Bull’s eye” for its prominent position on the face of Taurus.)

Astronomers estimate that the cluster is between 600 million and 700 million years old (a cosmic infant compared with our sun’s 4.6 billion years), and has already changed shape significantly in that time, thanks to the gravitational influence of other nearby clusters and objects. The authors of the new study wanted to learn more about those changes by studying the cluster’s “tails” — two stretched-out clumps of stars separated from the bulk of the cluster’s body, one aiming toward the Milky Way’s center and the other trailing away from it.

The Hyades star cluster, located in the head of Taurus, is slowly being pulled apart by an invisible monster.

Tidal tails, as astronomers call them, form naturally as the result of gravitational interactions between groups of stars. To see the tails at their clearest and most spectacular, scientists look to merging galaxies — like the swirly Antennae Galaxies — which gradually pull each other’s edges into wispy strings of starlight.

But recently, scientists observed tidal tails in stellar clusters, too. As stars within the clusters grow older and more massive, they jostle their neighbors, eventually pushing some stars toward the edge of the cluster. There, stars become more susceptible to the pull of even more massive objects within the galaxy, gradually leaving the cluster’s orbit and forming a tidal tail. The speed and trajectory of these tails can even point to the presence of objects that are invisible to telescopes, study lead author Tereza Jerabkova, an ESA research fellow, told Live Science.

“Stars [in tidal tails] may be seen to move faster in some direction, and this might indicate something is there which is attracting them,” Jerabkova said.

A cluster’s leading and trailing tails tend to contain the same approximate number of stars, but when Jerabkova and her colleagues mapped the Hyades cluster’s tails, they saw something surprising: The trailing tail had remarkably fewer stars in it than the leading tail. It looked as if the trailing tail was “dissolving” into space, the researchers wrote.

With computer simulations, the researchers tried to uncover what could be causing this mismatch. They concluded that the cluster and its tail were being “disrupted by a massive lump” of matter with a mass of 10 million suns, Jerabkova said, similar to how a large galaxy can disrupt a small one with its gravitational force. But even more puzzling, there was no “lump” — or any object at all — visible in the vicinity of the Hyades that could account for such a disturbance.
One possible explanation, the researchers said, is dark matter — the invisible, heavy stuff that makes up an estimated 27% of the universe’s total mass, according to NASA. Scientists suspect that “halos” of dark matter helped to shape galaxies like the Milky Way, and that vestiges (or “sub-halos”) of dark matter still exist scattered throughout the galaxy. It’s possible that the “lump” warping the Hyades cluster is in fact a dark matter sub-halo, invisibly bending the stars to its whims, the researchers said.

According to Jerabkova, that’s the best explanation for the Hyades’ wonky tails, given the current available data and understanding of physics. That’s an “important discovery,” she added, as it proves that data from Gaia and similar star-mapping missions can reveal not just the secrets of the stars and planets surrounding us — but the invisible structures that underlie our universe, as well.

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Todd

How can some planets be hotter than stars? We’ve started to unravel the mystery.

Until the early 2000s, the only known planets were located in our own neighbourhood, the Solar System. They broadly form two categories: the small rocky planets in the inner Solar System and the cold gaseous planets located in the outer part. With the discovery of exoplanets, planets orbiting stars other than the Sun, additional classes of planets were discovered and a new picture started to emerge. Our Solar System is by no means typical.

For example, data from the Kepler mission has shown that large, gaseous exoplanets can orbit very close to their star – rather than far away from it, as is the case in our Solar System, causing them to reach temperatures exceeding 1,000 Kelvin (727 degrees Celsius). These have been dubbed “hot” or “ultra-hot” Jupiters. And while most other exoplanets are smaller, between the size of Neptune and Earth, we don’t know much about their composition.

But how can hot, gaseous planets form and exist so close to their star? What kind of extreme physical processes happen here? Answers to those questions have large implications in our understanding of exoplanets and solar system planets. In our recent study, published in The Astrophysical Journal Letters, we have added another piece to the puzzle of planet formation and evolution.

Kelt-9 b

In essence, hot Jupiters are a window into extreme physical and chemical processes. They offer an incredible opportunity to study physics in environmental conditions that are near impossible to reproduce on Earth. Studying them enhances our understanding of chemical and thermal processes, atmospheric dynamics and cloud formation. Understanding their origins can also help us improve planetary formation and evolution models.

We are still struggling to explain how planets form and how elements, such as water, were delivered to our own Solar System. To find out, we need to learn more about exoplanet compositions by observing their atmospheres.

Observing atmospheres

There are two main methods to study exoplanet atmospheres. In the transit method, we can pick up stellar light that is filtered through the exoplanet’s atmosphere when it passes in front of its star, revealing the fingerprints of any chemical elements that exist there.

The other method to investigate a planet is during an “eclipse”, when it passes behind its host star. Planets also emit and reflect a small fraction of light, so by comparing the small changes in the total light when the planet is hidden and visible, we can extract the light coming from the planet.

Both types of observations are performed at different wavelengths, or colours, and since chemical elements and compounds absorb and emit at very specific wavelengths, a spectrum (light broken down by wavelength) can be produced for the planet to infer the composition of its atmosphere.

The secrets of Kelt-9 b

Artist’s illustration showing the bright star KELT-9 and its ultrahot planet, KELT-9b.

In our study, we used publicly available data, taken by the Hubble Space Telescope, to obtain the eclipse spectrum of this planet.

We then used open-source software to extract the presence of molecules and found there were plenty of metals (made from molecules). This discovery is interesting as it was previously thought that these molecules would not be present at such extreme temperatures – they would be broken apart into smaller compounds.

Subject to the strong gravitational pull from its host star, Kelt-9 b is “tidally locked”, which means that the same face of the planet permanently faces the star. This results in a strong temperature difference between the planet’s day and night sides. As the eclipse observations probe the hotter day-side, we suggested that the observed molecules could in fact be dragged by dynamic processes from the cooler regions, such as the night-side or from deeper in the interior of the planet. These observations suggest that the atmospheres of these extreme worlds are ruled by complex processes that are poorly understood.

Kelt-9 b is interesting because of its inclined orbit of about 80 degrees. This suggests a violent past, with possible collisions, which in fact is also seen for many other planets of this class. It is most likely that this planet formed away from its parent star and that the collisions happened as it migrated inwards toward the star. This supports the theory that large planets tend to form away from their host star in proto-stellar disks – which give rise to solar systems – capturing gaseous and solid materials as they migrate toward their star.

But we don’t know the details of how this happens. So it is crucial to characterise many of these worlds to confirm various scenarios and better understand their history as a whole.

Future missions

Observatories, such as the Hubble Space Telescope, were not designed to study exoplanet atmospheres. The next generation of space telescopes, such as the James Webb Space Telescope and the Ariel mission, will have much better capabilities and instruments specifically tailored for the rigorous observation of exoplanet atmospheres. They will allow us to answer many of the fundamental questions raised by the extremely hot-Jupiter planet class, but they will not stop there.

This new generation of telescopes will also probe the atmosphere of small worlds, a category that current instruments struggle to reach. In particular, Ariel, which is expected to launch in 2029, will observe about 1,000 exoplanets to tackle some of the most fundamental questions in exoplanet science.

Ariel will also be the first space mission to look in details at the atmosphere of these worlds. It should finally tell us what these exoplanets are made of and how they formed and evolved. This will be a true revolution.

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Todd

A mission to Uranus and Neptune could act as massive gravitational-wave detector

Uranus and Neptune have each only been visited by one spacecraft, Voyager 2.

What if one mission could study the gravitational waves triggered by some of the most violent events in the universe — on the way to observing the least-known planets of our solar system?

Planetary scientists are desperate for a new probes to Uranus and Neptune, since these ice giant worlds haven’t been visited since the Voyager mission flybys of the late 1980s. And while such a spacecraft would unearth a treasure trove of information about these solar system siblings, it could also peer much deeper into the universe, scientists say in a new analysis: By carefully monitoring variations in the radio signals from one or more such spacecraft, astronomers could potentially see the ripples in gravity caused by some of the most violent events in the universe.

Ice, ice baby

Poor Uranus and Neptune. The only close-up images we have of those outer worlds come to us from the Voyager 2 spacecraft, which swung by those planets on its “Grand Tour” in the late 1980s. Since then, we’ve sent probes to Mercury, missions to Jupiter and Saturn (including landing on the latter’s moon Titan), collected samples of asteroids and comets, and launched rover after rover to Mars.

But not Uranus or Neptune. Those worlds, now known as “ice giants” because water and ammonia ices dominate their composition, sit lonely in the outer fringes of our celestial neighborhood. There are no other worlds in the solar system quite like them, and an entire generation of planetary scientists have been able to study them with only ground-based telescopes and occasional glimpses from the Hubble Space Telescope.

Some of that delay has been out of our hands. Even Neptune at its closest sits over 2.7 billion miles (4.3 billion kilometers) away from the Earth.The extreme distance to Neptune and Uranus makes it incredibly hard to launch payloads there.

But an opportunity is coming soon, window during which Jupiter lines up just right to offer a much-needed velocity-boosting gravitational assist and cut travel time to the outer system. If we were to launch a mission in the early 2030s on a sufficiently powerful rocket, like NASA’s Space Launch System, a mission could reach Jupiter in a little less than two years for that speed boost. From there, a single spacecraft could separate into two components, one headed for Uranus (reaching it in 2042) and another for Neptune (achieving orbit a couple years after that).

Once in place, if luck prevails, those orbiters could maintain their station for over a decade, as the famed Cassini mission did at Saturn.

A shift to the left

During the long cruise to those icy destinations, those same space probes could also offer insight into a very different type of science, that of gravitational waves, as detailed in a paper recently uploaded to the preprint server arXiv.org and submitted to the Monthly Notices of the Royal Astronomical Society Letters.

During the course of the flight, scientists and technicians on the ground would constantly have to communicate with the spacecraft, updating its trajectory and checking its status. And conversely, the spacecraft would constantly radio back information to the Earth.

An artist’s depiction of gravitational waves.

Light waves bouncing back and forth along an extremely long path.

Sound familiar? On Earth, physicists reflect laser beams along miles-long tracks to measure passing gravitational waves. As the waves (which are ripples in the fabric of spacetime itself) pass through the Earth, they distort objects, compressing and stretching them in alternating series. Inside the detector, these waves subtly change the length between distant mirrors, affecting the path of light in the gravitational wave observatories by a minute amount (usually less than the width of an atom).

For radio communications from a distant space mission back to Earth, the effect is similar. If a gravitational wave passes through the solar system, it would change the distance to the spacecraft in a regular way, causing the probe to be ever-so-slightly closer to us, then farther away, then closer again. If the spacecraft was sending a transmission the entire cruise, we would see a resulting Doppler shift in the frequency of its radio communication. Having two such spacecraft acting at once would give astronomers sharper observations of that shift.

In other words, these far-flung space probes could do double-duty as the largest gravitational wave observatories in the world.

The greater universe

The biggest technological hurdle is the ability to measure the frequency of the spacecraft’s radio communications to an incredibly high precision. According to the recent research, our ability to measure this must be at least 100 times better than we could achieve for the Cassini mission to Saturn.

That sounds like a lot, but it’s been decades since Cassini was designed, and we’ve been improving our communication technologies the whole time. And physicists are currently designing their own space-based gravitational wave detectors, like the Laser Interferometer Space Antenna (LISA), which will require similar technology anyway. Since an ice giant mission is still almost a decade away, we could pour even more resources into developing the necessary technology.

If we can crack that level of sensitivity, then the extreme length of this gravitational wave detector “arm” (literally billions of times longer than our current detectors) could reveal a variety of extreme events in the universe. Due to its incredible length, this “ice giant observatory” would be sensitive to an entirely different class of events than what we can observe today. According to the research, during the lifespan of such a mission, the probes are likely to detect a few dozen mergers of black holes with extreme mass differences, and at least one merger of a supermassive black hole. These are events that we simply have not observed, and cannot observe, with current gravitational wave detectors.

Oh, and we would also get to learn about Uranus and Neptune.

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Todd

[Sean Robinson]

Explosion from the early universe illuminates secret black hole

This artistic impression illustrates a new black hole that was discovered through gravitational lensing using light from an ancient cosmic explosion.

Light coming from an explosion in the early universe has illuminated a black hole that astronomers think could expand their understanding of how the celestial objects form.

Three billion years ago, a gamma-ray burst (known as GRB 950830) exploded out into the universe. In 1995, astronomers observed the event, essentially peering “back in time” with the BATSE (Burst And Transient Source Experiment ) high-energy astrophysics experiment on the Compton Gamma-Ray Observatory, which was launched in 1991 on the space shuttle Atlantis. Now, astronomers used the light coming from the ancient explosion to detect an intermediate-mass black hole (IMBH), which are elusive and challenging to spot.

The light coming from the gamma-ray burst allowed the team to use a phenomenon called gravitational lensing to find an IMBH. This finding supports the existence of IMBHs, as they are so hard to detect that some scientists question whether or not they’re even real. This work also sheds light on how different types of black holes might form and how supermassive black holes (SMBH) could get so massive.

Intermediate-mass black holes are just what they sound like: celestial middleweights. The objects are fairly massive: larger than stellar black holes (SBH) but not as massive as SMBH, perhaps clocking in at between 100 and 100,000 times the mass of our sun.

However, these midsize black holes are especially challenging to detect “because they are smaller and less active than supermassive black holes; they do not have readily available sources of fuel, nor as strong a gravitational pull to draw stars and other cosmic material which would produce telltale X-ray glows,” according to NASA.

“If a black hole is not accreting matter, it is quite difficult to detect, as by name and nature they are black,” James Paynter, an astrophysicist at the University of Melbourne in Australia who led this research, told Space.com. “Only the effects of their gravity can betray the existence of a quiescent black hole.”

But, while IMBHs might not be easily spotted by luminous X-ray emissions like a supermassive black hole would, scientists in this new study were able to use gravitational lensing to do the trick. Gravitational lensing is a phenomenon that occurs when an object (like a black hole) acts like a lens, distorting the light coming from a faraway light source (like a cosmic explosion). This distortion signals astronomers that there must be a massive object in the way.

To go a step further and determine what type of object is causing this lensing, the team had to determine its mass. Because the object’s mass falls within the range of an IMBH, they decided it was the most likely possibility. They were also able to weed out contenders like globular clusters for not being dense enough and dark matter haloes for not being compact enough to cause gravitational lensing.

By discovering the IMBH using this technique, it “tells us something about how common they [IMBH] are,” Rachel Webster, an astronomer at the University of Melbourne and co-author of this study, told Space.com. “If they were very, very rare then we would be most unlikely to see even one case of gravitational lensing. It’s all about statistics and probability.”

This IMBH detection could also reveal information about their larger cousins, SMBH. “It is important to discover these objects to fill the observational gap between stellar black holes (SBH) and SMBH,” Paynter said. “Currently, we do not know how SMBH are able to grow to such huge masses within the age of the universe. There is simply not enough stuff for them to accrete, nor enough time.”

The clue to the SMBH puzzle may lie in IMBHs, scientists hope. “If a seed population of IMBHs exist, it begins to fill in this gap. Where the IMBHs came from is another matter… they may be formed from the merger/collapse of massive, Hydrogen-pure stars in the early universe, or they may be older, primordial black holes formed during the very first phases of the universe,” Paynter added.

While this work is a step forward in not only proving the existence of IMBH, but in exploring how different types of black holes develop and exist out in the cosmos, there is still much to be explored and learned about this IMBH.

“We now don’t know if this IMBH is wandering the cosmos alone, or if it is bound to a galaxy or cluster of stars. So while we are able to estimate the prevalence of these objects in the universe, we can’t pinpoint them to a location or specific ‘habitat,'” Paynter said.

• This reply was modified 3 years, 9 months ago by Sean Robinson.

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Todd

A remnant of a protoplanet may be hiding inside Earth

A protoplanet slammed into the Earth about 4.5 billion years ago, knocking loose a chunk of rock that would later become the moon. Now, scientists say that remnants of that protoplanet can still be found, lodged deep inside Earth, Science Magazine reported.

If remains of the protoplanet, known as Theia, did stick around after the impact, that may explain why two continent-size blobs of hot rock now lie in the Earth’s mantle, one beneath Africa and the other under the Pacific Ocean. These massive blobs would stand about 100 times taller than Mount Everest, were they ever hauled up to Earth’s surface, Live Science previously reported.

Theia’s impact both formed the moon and transformed Earth’s surface into a roiling magma ocean, and some scientists theorize that the blobs formed as that ocean cooled and crystalized, Science reported. Others think the blobs contain Earth rocks that somehow escaped the effects of the collision and nestled, undisturbed for millions of years, near the planet’s center.

But last week, at the Lunar and Planetary Science Conference, Qian Yuan, a doctoral student in geodynamics at Arizona State University (ASU) Tempe, presented an alternate hypothesis.

more in link…

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Rare daytime fireball meteor creates massive sonic boom over UK

The meteor was bright enough to be seen during the day.

An artists impression of a meteor breaking apart during the daytime.

A rare daytime fireball meteor triggered a loud sonic boom across parts of the United Kingdom and France over the weekend.

The sonic boom occurred at 2:50 p.m. local time on Saturday (March 20) and was reportedly heard in southwest England, Wales and northern France, according to Sky News. At first, most people assumed that the noise was the result of fighter jets, but the Ministry of Defence quikcly announced that this couldn’t have been the case, according to the BBC.

However, a handful of people on Twitter said they had witnessed a bright flash of light across the sky at the same time, and thanks to satellite images, it was later confirmed to be a fireball meteor, according to the BBC.

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Interstellar interloper 2I/Borisov may be the most pristine comet ever observed

The rogue comet likely never encountered a star before it

The first known interstellar comet to visit our solar system may be the most pristine ever found, never passing near a star until visiting our own, researchers say.

In 2019, scientists discovered the comet 2I/Borisov as it streaked into the solar system. The comet’s speed and trajectory revealed it was a rogue comet from interstellar space, making it the first known interstellar comet and the second known interstellar visitor after pancake-shaped 1I/’Oumuamua.

Now scientists have found two new ways in which 2I/Borisov is unlike any known comet. They detailed their findings online March 30 in two studies, one published in the journal Nature Communications and another study in the journal Nature Astronomy.

More in link…

An artist’s impression of what the surface of the interstellar comet 2I/Borisov might look like.

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Rocket, Todd

Climate explained: How particles ejected from the sun affect Earth’s climate

Earth’s magnetic field protects us from the solar wind, guiding the solar particles to the polar regions

When the Sun ejects solar particles into space, how does this affect the Earth and climate? Are clouds affected by these particles?

When we consider the sun’s influence on Earth and our climate, we tend to think about solar radiation. We are acutely aware of the skin-burning dangers of ultraviolet, or UV, radiation.

But the sun is an active star. It also continuously releases what is known as “solar wind,” made up of charged particles, largely protons and electrons, that travel at speeds of hundreds of kilometres per hour.

Some of these particles that reach Earth are guided into the polar atmosphere by our magnetic field. As a result, we can see the southern lights, aurora australis, in the southern hemisphere, and the northern equivalent, aurora borealis.

The southern lights, less-photographed than their northern counterparts, are seen from the air in a recent charter flight from New Zealand.

This visible manifestation of solar particles entering Earth’s atmosphere is a constant reminder there is more to the sun than sunlight. But the particles have other effects as well.

Solar particles and ozone

When solar particles enter the atmosphere, their high energies ionise neutral atmospheric nitrogen and oxygen molecules, which make up 99% of the atmosphere. This “energetic particle precipitation,” named because it’s like a rain of particles from space, is a major source of ionisation in the polar atmosphere above 30 km altitude — and it sets off a chain of reactions that produces chemicals that facilitate the destruction of ozone.

The impact of solar particles on atmospheric ozone was first observed in 1969. Since the early 2000s, thanks to new kinds of satellite observations, we have seen growing evidence that solar particles play an important part in influencing polar ozone. During particularly active times, when the Sun releases large amounts of particles into space, up to 60% of ozone at altitudes above 50 km can be depleted. The effect can last for weeks.

Lower down in the atmosphere, below 50 km, solar particles are important contributors to the year-to-year variability in polar ozone levels, often through indirect pathways. Here, solar particles again contribute to ozone loss, but a recent discovery showed they also help curb some of the depletion in the Antarctic ozone hole.

How ozone affects the climate

Most of the ozone in the atmosphere resides in a thin layer at altitudes of 20-25 km — the “ozone layer.”

But ozone is everywhere in the atmosphere, from the Earth’s surface to altitudes above 100 km. It is a greenhouse gas and plays a key role in heating and cooling the atmosphere, which makes it critical for climate.

In the Southern Hemisphere, changes in polar ozone are known to influence regional climate conditions.

Solar particles ionise nitrogen and oxygen molecules in the atmosphere, which leads to other chemical reactions that contribute to ozone destruction.

Its depletion above Antarctica had a cooling effect, which in turn pulled the westerly wind jet that circles the continent closer. As the Antarctic hole recovers, this wind belt can meander further north and affect rainfall patterns, sea-surface temperatures and ocean currents. The Southern Annular Mode describes this north-south movement of the wind belt that circles the southern polar region.

Ozone is important for future climate predictions, not only in the thin ozone layer, but throughout the atmosphere. It is crucial we understand the factors that influence ozone variability, be it man-made or natural like the sun.

The sun’s direct influence

The link between solar particles and ozone is reasonably well established, but what about any direct effects solar particles may have on the climate?

We have observational evidence that solar activity influences regional climate variability at both poles. Climate models also suggest such polar effects link to larger climate patterns (such as the Northern and Southern Annular Modes) and influence conditions in mid-latitudes.

The details are not yet well understood, but for the first time the influence of solar particles on the climate system will be included in climate simulations used for the upcoming Intergovernmental Panel on Climate Change (IPCC) assessment.

Through solar radiation and particles, the Sun provides a key energy input to our climate system. While these do vary with the Sun’s 11-year cycle of magnetic activity, they can not explain the recent rapid increase in global temperatures due to climate change.

We know rising levels of greenhouse gases in the atmosphere are pushing up Earth’s surface temperature (the physics have been known since the 1800s). We also know human activities have greatly increased greenhouse gases in the atmosphere. Together these two factors explain the observed rise in global temperatures.

What about clouds?

Clouds are much lower in the atmosphere than where most solar particles penetrate. Particles know as galactic cosmic rays (coming from the centre of our galaxy rather than the sun) may be linked to cloud formation.

It has been suggested cosmic rays could influence the formation of condensation nuclei, which act as “seeds” for clouds. But recent research at the CERN nuclear research facility suggests the effects are insignificant.

This doesn’t rule out some other mechanisms for cosmic rays to affect cloud formation, but thus far there is little supporting evidence.

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Todd

Uranus is belching X-rays and is weirder than we ever thought

The more scientists study it, the weirder Uranus gets.

The newest mystery to add to the planet’s repertoire? Astronomers have detected X-rays from the strange world — and while some of the signal may be reflected emissions from the sun, some appear to be coming from the planet itself, according to a NASA statement.

That’s according to new research that analyzed observations of Uranus gathered by NASA’s Chandra X-ray Observatory in 2002 and 2017.

A composite image of the planet Uranus shows 2002 X-ray emission in pinkish purple.

Plenty of solar system objects emit X-rays — everything from Venus to Saturn to moons of Jupiter, the scientists write in a paper describing their research. In fact, of the solar system’s planets, only little-studied Uranus and Neptune were missing from the list.

The team of astronomers were particularly drawn to study Uranus in X-rays because the planet’s alignments are quite jumbled: the planet lies on its side and the axis of its magnetic field is akimbo from both the orbital plane and the spin axis. The skewed axes may trigger particularly complicated auroras, which can emit X-rays.

So the scientists decided to dig into the scant Chandra observations of Uranus — just three segments of data, one from August 2002 and two from November 2017. The 2002 and 2017 observations also come from different instruments on the telescope, and in the 2017 data, the researchers can’t clearly mark which X-rays come from the planet itself and which from elsewhere in the detector’s view.

A composite image of Uranus shows both X-ray emissions and infrared emissions against an optical view of the planet.

All that means that the scientists, as usual, want more observations. But according to the researchers, both patches of data appear to show X-ray emissions from the strange planet — and more than would be expected solely from the planet’s atmosphere scattering off X-ray emissions from the sun.

If some of the X-rays the researchers detected are indeed coming from Uranus itself, rather than reflected emissions from the sun, a few phenomena could be at play, the scientists wrote. Saturn’s rings produce X-ray fluorescence when hit by charged particles from the sun, and Uranus’ two sets of rings may do the same. Or, the X-rays may come from auroras on Uranus, as they do on Jupiter, although scientists aren’t positive what would trigger the auroras themselves.

Scientists hope that future observations by Chandra may help determine what’s happening at Uranus. Missions yet to launch may also be able to study the planet’s X-ray emissions, particularly the European Space Agency’s Advanced Telescope for High Energy Astrophysics (ATHENA), due to launch in 2031, or the Lynx X-ray Observatory mission that NASA is considering for launch after its Nancy Grace Roman Telescope.

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Todd

[Sean Robinson]

Astronomers find the ‘safest place’ to live in the Milky Way

Scientists found the safest place for life in the Milky Way is about 26,000 light-years from its center.

Astronomers have searched the entire Milky Way to identify the safest places to live. It turns out, we’re in a pretty good spot.

But if the past year has made you feel ready to relocate to another planet, you might want to look toward the center of the galaxy, according to the new research.

The new findings were made by a group of Italian astronomers, who studied locations where powerful cosmic explosions may have killed off life. These explosions, such as supernovas and gamma-ray bursts, spew high-energy particles and radiation that can shred DNA and kill life. By this logic, regions that are more hospitable to life will be the ones without frequent explosions, the astronomers reasoned.

“Powerful cosmic explosions are not negligible for the existence of life in our galaxy throughout its cosmic history,” said lead author on the new study, Riccardo Spinelli, astronomer at the University of Insubria in Italy. “These events have played a role in jeopardizing life across most of the Milky Way.”

In addition to finding the deadliest hotspots, the astronomers also identified the safest places throughout the galaxy’s history, going back 11 billion years. The results show that we’re currently at the edge of a wide band of hospitable real estate. But in the Milky Way’s youth, the galaxy’s edges were a safer bet.

Galactic Goldilocks zone

Many factors make a planet habitable. For instance, planets need to be in a Goldilocks zone, where heat and activity from their host star isn’t too much or too little — it’s just right. But in addition to these local conditions, life also has to combat harmful radiation coming from interstellar space.

Powerful cosmic events, such as supernovas and gamma-ray bursts, stream dangerous, high-energy particles at nearly the speed of light. Not only can they kill all the lifeforms we know about, but these particles can also strip entire planets of their atmospheres. After such an event, the scientists believe that planets orbiting nearby star systems would be wiped clear of life.

“For planets very close to the stellar explosion it is plausible that there is a complete sterilization,” Spinelli told Live Science. “In those far away, a mass extinction is more likely.”

The authors wrote in the study that a nearby gamma-ray burst may have played a leading role in the Ordovician mass extinction event around 450 million years ago — the second largest in Earth’s history. While there is no concrete evidence linking a specific gamma-ray burst to this extinction event, the authors think it could be likely, given Earth’s position in the galaxy.

Searching for safety

Using models of star formation and evolution, the astronomers calculated when specific regions of the galaxy would be inundated with killer radiation. Early on in the galaxy’s history, the inner galaxy out to about 33,000 light-years was alight with intense star formation, which rendered it inhospitable. At this time, the galaxy was frequently rocked by powerful cosmic explosions, but the outermost regions, which had fewer stars, were mostly spared these cataclysms.

Until about 6 billion years ago, most of the galaxy was regularly sterilized by massive explosions. As the galaxy aged, such explosions became less common. Today, the mid regions, forming a ring from 6,500 light-years from the galaxy’s center to around 26,000 light-years from the center, are the safest areas for life. Closer to the center, supernovas and other events are still common, and in the outskirts, there are fewer terrestrial planets and more gamma-ray bursts.

Luckily for us, our galactic neighborhood is getting more and more life-friendly. In the long-term galactic future, there will be fewer extreme events nearby that could cause another mass extinction.

The new paper’s conclusions seem reasonable at first glance, Steven Desch, an astrophysicist at Arizona State University, told Live Science.

“I’m pleased to note that they do seem to put [the research] in a rigorous framework and have realistic expectations about what a gamma ray burst would do, and account for factors that sometimes people forget,” such as how the energy and material released by gamma-ray bursts isn’t equal in all directions, said Desch, who was not involved with the new work. “I haven’t gone through their numbers in detail, but at first glance it’s reasonable.”

The new research, published in the March issue of the journal Astronomy and Astrophysics, might one day help astronomers decide where to search for habitable exoplanets. But for now technology limits astronomers to only searching nearby areas, Desch said.

• This reply was modified 3 years, 9 months ago by Sean Robinson.

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Todd

Dark matter could be made of black holes from the beginning of time

An analysis of ripples in space-time suggests the mysterious substance consists of primordial black holes.

Dark matter could consist of ancient black holes.

Dark matter, the mysterious substance that exerts gravitational pull but emits no light, might really consist of vast concentrations of ancient black holes created at the very start of the universe, according to a new study.

That conclusion comes from an analysis of the gravitational waves, or ripples in space-time, produced by two distant collisions between black holes and neutron stars.

The ripples — labeled GW190425 and GW190814 — were detected in 2019 by the Laser Interferometer Gravitational-Wave Observatory (LIGO) in Washington and Louisiana, and the Virgo Interferometer near Pisa, Italy. A previous analysis suggested the ripples were produced by collisions between black holes between 1.7 and 2.6 times the mass of our sun and either a smaller neutron star or a much larger black hole.

But that would make one of the objects in each collision what astrophysicists call a solar-mass black hole, with roughly the mass of the sun.

“Solar-mass black holes are quite mysterious, as they are not expected from conventional astrophysics,” such as the star explosions, or supernovas, that crush larger stars into black holes, study lead author, Volodymyr Takhistov of the University of California, Los Angeles, told Live Science in an email.

Instead, the authors propose in the study, published Feb. 16 in the journal Physical Review Letters, these solar mass black holes may be “primordial” black holes created during the Big Bang. Or they might have formed later when neutron stars were transmuted into black holes — either after swallowing up primordial black holes, or after absorbing certain proposed types of dark matter, the mysterious matter that exerts gravitational pull does not interact with light, Takhistov said.

Primordial black holes

Primordial black holes, if they exist, were likely created in vast numbers in the first second of the Big Bang about 13.77 billion years ago. They would have come in all sizes — the smallest would have been microscopic and the largest tens of thousands of times the mass of our sun..

Calculations show the smallest would have “evaporated” by now, by emitting quantum particles through a process known as Hawking radiation, so that only primordial black holes with masses greater than 10^11 kilograms — about the mass of a small asteroid — would still exist today.

If they did exist, these ancient black holes could make up the immense halos of “dark matter” that fringe galaxies, some astrophysicists think.

The researchers wanted to learn if they could distinguish primordial black holes from black holes that had formed from neutron stars, the glimmering remnants of supernovas left behind when their parent stars exploded after using up all their hydrogen in nuclear fusion reactions.

Astrophysicists have calculated that stars smaller than about five times the mass of the sun collapse to leave behind a neutron star of ultra-dense matter, with roughly the mass of our sun packed into a ball the size of a city, Live Science reported.

In this theory, the intense gravity of some neutron stars would have continuously attracted particles of dark matter; eventually their gravity would have become so great that the neutron star and dark matter would have collapsed together into a black hole, the new study suggests.

An alternative proposed by the study is that a neutron star might have attracted and merged with a small primordial black hole, which then settled at the neutron star’s centre of gravity and fed off the surrounding matter until only the black hole remained.

Gravitational waves

Takhistov and his colleagues reasoned that black holes transmuted from neutron stars would have to follow the same mass distribution of the neutron stars they originated from, which depends on the sizes of their parent stars.

Taking that into account, they looked at the data from the 50 or so gravitational wave detections made to date, and found that just two — GW190425 and GW190814 — involved objects with the right masses to be primordial black holes, the study authors wrote.

The research is not conclusive: it’s still possible those two collisions involved neutron stars of the masses detected, or black holes transmuted from neutron stars of those sizes. But the mass distribution of neutron stars theorized to exist in the universe makes that unlikely, the authors wrote.

“Our work advances a powerful test to understand their origin and relation with dark matter,” Takhistov said. “In particular, this test demonstrates that black holes significantly heavier than about 1.5 solar-masses are very unlikely to be ‘transmuted’ black holes from neutron star disruptions.”

And if that’s the case, it hints that primordial black holes might really exist, and that they could be a component of dark matter, according to the study.

The method will become more accurate as more gravitational wave detections are made, Takhistov said: “The test is statistical in nature, so gathering more data will allow for a better understanding.”

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Todd

Dark matter ‘annihilation’ may be causing the Milky Way’s center to glow

Dark matter could explain the mysterious light.

A mysterious glow in the center of the Milky Way.

A mysterious glow coming from the center of the Milky Way might be caused by annihilating dark matter — elusive matter that emits no light.

According to new research, heavy dark matter particles may be destructively colliding at the center of the galaxy, creating elementary particles, as well as gamma rays — the unexplained light seen emanating from the galactic center.

The source of this unexplained light, called the galactic center excess (GCE), has been debated by scientists ever since it was discovered in 2009. When analyzing data from NASA’s Fermi Gamma-ray Space Telescope, scientists noticed a faint glow of gamma rays that couldn’t be explained by known sources. In the years since, scientists have proposed a range of sources, from dark matter to more conventional sources, such as extremely fast-spinning stars called millisecond pulsars.

Now, a new look at over a decade’s worth of data from the Fermi telescope, combined with data from an experiment on the International Space Station and observations of nearby dwarf galaxies, suggests that heavy dark matter particles at the center of the galaxy may explain the glow.

“I think the most interesting finding is that dark matter can explain the galactic center excess,” while also matching observations from nearby galaxies, said study lead author Mattia di Mauro, a researcher of the Turin division of the National Institute for Nuclear Physics in Italy. “This result has never been found with a model where everything, dark matter density and particle physics model, is taken consistently.”

In the new analysis, di Mauro carefully studied the excess gamma ray light to map its position, shape and energy levels. The results, published on March 22 in the journal Physical Review D, found the glow to be fairly spherical and symmetrically centered in the middle of the Milky Way.

In a follow-up study, posted to the preprint database arXiv, di Mauro and collaborator Martin Wolfgang Winkler, a researcher at Stockholm University and The Oskar Klein Centre for Cosmoparticle Physics in Sweden, investigated what the gamma ray glow could reveal about these dark matter particles. By looking for similar gamma ray glows from dwarf spheroidal galaxies and observations from an experiment aboard the International Space Station of excess positrons, or the positively charged antimatter partners of electrons, coming from those galaxies, the researchers were able to constrain the mass and cross-section of the dark matter candidates.

The results suggest that the dark matter particles have a mass of about 60 gigaelectron volts — roughly 60 times that of a proton. When these dark matter particles collide, they annihilate into muons and antimuons, or electrons and positrons. If this hypothesis is correct, dark matter particles like these could be made and detected here on Earth with existing experiments, such as the Large Hadron Collider, and will help scientists narrow their search.

However, not all scientists are convinced by the new results. Several groups have previously ruled out GCE contributions by dark matter particles that are less massive than 400 gigaelectron volts. Other skeptics argue that the excess light is from undiscovered stars, as the light distribution maps closely to where stellar populations should be.

“They have opted for not including the [stellar distributions] in their analysis, which to me is not understandable from both a statistical and physical point of view,” said Oscar Macias Ramirez, an astronomer at the University of Amsterdam who was not involved in the new research. “From the physics point of view, one should not forget that there are just too many potential gamma-ray emitters that live with stars.”

If the excess light is indeed from millisecond pulsars or other stars, Macias Ramirez said, upcoming radio telescopes, such as the Square Kilometer Array in the Australian Outback, X-ray telescopes or high-energy gamma ray telescopes, such as the Cherenkov Telescope Array currently under construction in Chile’s Atacama Desert, could detect these stellar populations and close the debate within the next five years.

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Todd

Hubble telescope reveals a gorgeous, detailed new view of the Veil Nebula

With new processing techniques, NASA’s Hubble space telescope has captured the beautiful Veil Nebula in the finest detail ever.

NASA’s Hubble Space Telescope has snapped a stunning photo of the Veil Nebula in more exquisite detail than ever before.

The new image, released by NASA on April 2, was captured using new processing techniques that highlight small details like the nebula’s delicate thread and filaments of ionized gas, NASA said in a statement. Observations were taken by Hubble’s Wide Field Camera 3 using five different filters. New post-processing methods were used to further enhance emissions from doubly ionized oxygen (seen in the image in blue), ionized hydrogen and ionized nitrogen (seen in red).

This is not the first time the Veil Nebula has been featured in a Hubble image release. The space telescope captured a less detailed, but still beautiful image of the nebula in 2017. The Veil Nebula exists about 2,100 light-years from Earth in the constellation of Cygnus, the swan, which makes it relatively close to Earth compared to other astronomical objects, NASA said in the statement.

The Veil Nebula is part of the nearby Cygnus Loop, which is a remnant of a supernova created about 10,000 years ago by the death of a star 20 times the mass of our sun. The cataclysmic release of energy following the star’s death resulted in the Veil Nebula’s delicate filaments of ionized gas.

Although only a small portion of the nebula was captured in this Hubble image, you can see larger glimpses of the nebula in Hubble’s Caldwell Catalog.

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njerry, Todd

Sean Robinson wrote:

An artists impression of a meteor breaking apart during the daytime.

Ok, I understand artist impressions of interstellar objects or events. But NO ONE could get a picture of an event which occurred over UK and France during the day?

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Biden proposes $24.7 billion NASA budget in 2022 to support moon exploration and more

It’s a $1.5 billion increase over NASA’s 2021 budget.

More than two months after taking office, President Joe Biden has offered a first look at his budget priorities, and the signs for NASA are generally promising.

The administration today (April 9) unveiled a so-called “skinny budget” for fiscal year 2022, which begins on Oct. 1. Biden’s proposed budget requests $24.7 billion for NASA, a $1.5 billion increase from 2021. The skinny budget represents only top-line budget items, a traditional practice for the first year of a new presidential administration because of how the inauguration and Congress’ budgetary calendar align.

NASA Acting Administrator Steve Jurczyk welcomed the proposals in an agency statement. “This $24.7 billion funding request demonstrates the Biden Administration’s commitment to NASA and its partners who have worked so hard this past year under difficult circumstances and achieved unprecedented success,” he said.

more in link…

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The Great North American Solar Eclipse of 2024 is just three years away

April 8, 2024: Get ready to look up.

Three years from today, on Monday, April 8, 2024, more than half a billion people across North America will likely take a few moments out of their daily routines, and gaze up into the sky to get a view of one of nature’s great shows: an eclipse of the sun.

And those who are fortunate to be positioned along a narrow path stretching across northern Mexico through parts of 15 U.S. states, there will come the opportunity to what many have come to call the most spectacular of celestial roadshows — a total solar eclipse.

Many readers certainly will remember “The Great American Eclipse of 2017.” That event received considerable media attention and rightly so. It was the first total eclipse of the sun to be visible from the contiguous (48) United States since 1979, the first since 1918 to go from coast-to-coast and the first total solar eclipse to be visible from the United States in the 21st century. And it was also the very first time in modern history that the path of totality was visible solely from within the confines of the United States and no other country.

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Director Neil Burger’s ‘Voyagers’ launches a colony ship to the stars

Writer-director Neil Burger is well known for his provocative cinematic projects, most notably 2006’s period-set magician movie “The Illusionist,” 2011’s psychological thriller “Limitless,” and a trio of “Divergent” films adapted from author Veronica Roth’s young adult sci-fi novels.

Now Burger has his eyes fixed on the stars with his new science fiction adventure flick, “Voyagers,” which revolves around the perils inside a generation spaceship carrying 30 home-grown candidates on a one-way mission to settle an exoplanet 86 years from Earth.

Lionsgate will release “Voyagers” nationwide on April 9. The film’syouthful cast includes Tye Sheridan, Lily-Rose Depp, Fionn Whitehead, Chanté Adams, Isaac Hempstead Wright, Viveik Kalra, Archie Madekwe, Quintessa Swindell, Madison Hu, and Colin Farrell. The premise finds the crew discovering that they’re being drugged with an emotional suppressant called “The Blue,” and centers on the heightened chaos that ensues when they stop drinking their medicine.

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Hubble telescope finds rare double quasars in ancient galactic collisions

With a little help from Gaia and Sloan Digital Sky Survey.

An artist’s impression of the light emitted from the two quasars nestled in colliding galaxies.

NASA’s Hubble Space Telescope has captured not one but two pairs of distant quasars that existed some 10 billion years ago, a new study reports.

According to the team leading the research, the discovery was like finding a needle in a haystack, as the chance of locating a double quasar compared to a single quasar is just one in 1,000.

Imagery captured by the long-serving space telescope shows that the quasars within each pair are only about 10,000 light-years apart. For comparison, our sun is 26,000 light-years away from the supermassive black hole at the heart of the Milky Way. The researchers, led by Nadia Zakamska of Johns Hopkins University in Baltimore, Maryland, believe that the quasars are knitted so closely to each other because each pair lies at the center of two galaxies in the midst of a smashup.

A quasar is an intense emission of light from the center of a galaxy that’s fuelled by the gluttonous supermassive black hole at its core. “Quasars make a profound impact on galaxy formation in the universe,” Zakamska said in a statement released on April 6.

When two galaxies collide, their intense gravity causes the structures to become warped. More material is funneled into their respective black holes as a result, igniting their quasars. Over time, the intense radiation fuels galactic winds that strip away most of the gas from the merging galaxies.

This process results in the formation of an elliptical galaxy. A similar sequence is predicted to happen a few billion years from now when the Milky Way merges with its nearest galactic neighbor, the Andromeda galaxy.

More than 100 double quasars have been discovered in merging galaxies, though none are as old as the two pairs found in this study. The newly discovered quasars are from an era associated with an abundance of quasar formation, about 10 billion years ago. Astronomers had previously suggested there should be myriad dual quasars during that time, but none had been detected until now.

These images captured by the Hubble Space Telescope reveal two pairs of quasars. The pair on the left are catalogued as J0749+2255 (taken January 5 2020) and the pair on the right as J0841+4825 (taken on November 30 2019). Both images were taken in visible light with Wide Field Camera 3.

“This truly is the first sample of dual quasars at the peak epoch of galaxy formation with which we can use to probe ideas about how supermassive black holes come together to eventually form a binary,” Zakamska said.

The discovery of these four quasars not only informs researchers on the merging of supermassive black holes in the early universe, but also highlights the benefits of employing a variety of techniques to detect and image elusive dual quasars, study team members said.

Although Hubble is the only telescope with a high enough resolution to distinguish these two close quasar pairs, its sharp eye wasn’t quite good enough to locate them on its own. Astronomers needed to point Hubble in the right direction, and for that they enlisted the help of the European Space Agency’s star-mapping Gaia satellite and the ground-based Sloan Digital Sky Survey to compile a list of possible candidates for Hubble to investigate.

When the researchers then observed the first four targets with Hubble, they found that two of the targets were actually two pairs of close quasars. The researchers said it was a “light bulb moment” that reaffirmed their plans to use Hubble, Sloan and Gaia to search for quasar duos.

“The new technique can not only discover dual quasars much further away, but it is much more efficient than the methods we’ve used before,” said Xin Liu of the University of Illinois at Urbana-Champaign, who was also part of the study.

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Todd

[Rocket]

Sean Robinson wrote:

the chance of locating a double quasar compared to a single quasar is just one in 1,000.

Is a double quasar like a double rainbow?

The Great North American Solar Eclipse of 2024 is just three years away

A local DJ was talking about this last week. I did not realize that Rochester will be smack dab in the middle of it.

• This reply was modified 3 years, 9 months ago by Rocket.

[Sean Robinson]

Party at Rocket’s place in 3 years! Rent paid in empty beer cans!
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Astronomers detect a bright-blue bridge of stars, and it’s about to blow

It’s an entirely new region of the Milky Way.

The Milky Way galaxy.

Astrophysicists have found a new region of the Milky Way, and it’s filled with searingly hot, bright-blue stars that are about to explode.

The researchers were creating the most detailed map yet of the star-flecked spiral arms of our galactic neighborhood with the European Space Agency’s (ESA) Gaia telescope when they discovered the region, which they have named the Cepheus spur, they reported in a new study.

Nestled between the Orion Arm — where our solar system is— and the constellation Perseus, the spur is a belt between two spiral arms filled with enormous stars three times the mass of the sun and colored blue by their blistering heat.

Astronomers call these giant, blue stars OB stars due to the predominantly blue wavelengths of light that they emit. Stars of this type are the rarest, hottest, shortest-living and largest stars in the entire galaxy. The violent nuclear reactions taking place inside their hearts make them six times hotter than the sun. And the enormous stellar explosions that end their lives — called supernovas — scatter the heavy elements essential for complex life far into the galaxy.

“OB stars are rare, in a Galaxy of 400 billion stars there might be less than 200,000,” study co-author Michelangelo Pantaleoni González, a researcher at the Spanish Astrobiology Center (CAB), told Live Science. “And as they’re responsible for the creation of a lot of the heavy elements, they can really be seen as the chemical enrichers of the galaxy. It’s because of stars like these, dead long ago, that the geochemistry of our planet was complex enough for biochemistry to arise.” Wherever we find blue stars, we find the most active and most “alive” regions of the galaxy, according to the researchers.

The researchers compiled their star map by triangulating the stars’ distances to Earth using a technique called stellar parallax. By comparing the apparent positions of the stars, observed from different perspectives during Earth’s orbit around the sun, astronomers can calculate the distances to the stars themselves. Using this technique, along with data from the ESA’s Gaia telescope, the team mapped out stars at distances beyond any of those charted before and in areas of space previously thought to be empty.

“After months of work, we saw this beautiful map for the first time,” Pantaleoni González said. “I felt like an explorer of the enlightenment, tracing the first accurate maps of our world — just now on another scale. I felt extremely humble and tiny seeing how vast our stellar neighborhood is.”

The scientists proved that the new region was a part of the spiral galactic disk comprising most of our galaxy’s material, and not just a random alignment of stars, by observing them moving consistently in the same direction.

They also suspect that looking at the spur’s position, which is slightly above the galactic disk, could provide some tantalizing hints about the Milky Way’s past.

“If we are living in a galaxy with corrugations, which are slight vertical variations or ripples across its disk, it could point to a history of violent evolution for our galaxy,” Pantaleoni González said. “They could be signs of past collisions with other galaxies.”

The next step for the researchers will be to put additional OB stars into a more precise map, which they hope will produce even more insights into our Galaxy’s structures.

• This reply was modified 3 years, 9 months ago by Sean Robinson.

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Curious Kids: Could octopuses evolve until they take over the world and travel to space?

Michael, aged 14, asks:

If the faster part of human evolution is over, and squids and octopuses continue to evolve, could there be an apocalypse where the cephalopods take over the world?

If they continue to get smarter, octopuses would be much more suited as conquerors of Earth because they could live nearly anywhere. They have abilities similar to what we would call superpowers: they can fit into any hole that fits their beak, they can camouflage, they can regenerate their lost limbs and more. If and when they eradicate humans, they would be better suited to space travel. In orbit, they could maneuver much more easily and fit in smaller spaces.

So if they simply started evolving a smarter brain, what stops all this from happening? Why has this not happened already? Why have so few creatures evolved an intelligent brain?

As Michael points out, octopuses are famous for their alien-like abilities, from regrowing damaged arms to changing their skin color and texture. They use this color-shifting power to camouflage and, interestingly, as a strange visual language to talk to other octopuses.

A little-known fact is they actually belong to a category of animals (phylum) called Mollusca, which is largely made up of snails. Yep, octopuses are like souped-up snails who lost their shells and grew a rather large brain. The coolest thing about them is their intelligence, which evolved completely independently from our own.

They use tools to solve problems (like us) and they can open child-proof containers (not always like us). And just last week, research found a cuttlefish (another cephalopod, cousins of octopuses) passed an intelligence test designed for toddlers that showed they have advanced self control.

Humans no doubt have a lot more to learn about what these mysterious creatures are capable of. But what we do know can start to answer Michael’s excellent question: could octopuses one day rule the world?

(Before we go further we should state the plural of octopus is “octopuses” — not necessarily “octopi” — given the word has Greek rather than Latin routes.)

Big-brained but short-lived

Let’s first consider their nervous system. Like us, octopus have large brains compared to their body size – easily the biggest of all invertebrates (animals without a backbone) and of comparable size to many vertebrates, such as frogs.

It is, however, hard to compare brain size between marine animals and land animals, because the laws of physics differ in water and air. Animals are weightless in water but on land body shape and size is limited by gravity.

An octopus brain is made up of about 500 million brain cells (neurons). This is seven times more than a mouse and about the same as a marmoset monkey. Humans, on the other hand, have 86 billion brain cells.

Testing octopus intelligence can be a problem, because the animals frequently outsmart scientists. For example, scientists can struggle to get an octopus to solve a maze, because they often climb out and crawl over the top to reach their food reward. And that’s assuming they haven’t already escaped from their aquarium home and are crawling around the lab.

Unlike us though, octopuses don’t live for very long. The giant Pacific octopus might live up to five years, but most live for just a year and some as little as six months. They hatch from eggs fully formed and ready to go. They never see their parents and have to learn everything on their own.

So yes, octopuses have big brains and are crazy-smart. But could they take over the world if they kept evolving?

Why they evolve so slowly

Compared to other species, octopuses actually evolve really, really slowly. There are about 300 different species of octopus, which have been around for at least 300 million years. In that time, they haven’t changed much.

Modern humans, by comparison, have only existed for 200,000 years and in that time, have taken over the planet (and badly damaged it in the process).

Evolution occurs when the DNA code is gradually changed in small steps over vast amounts of time. But octopus have a unique method of actively editing their RNA molecules instead. RNA are messages sent from DNA, which tells genes what to do and when.

The ability to edit RNA means they can adapt quickly to new problems, bypassing the need for long-term changes to occur in the DNA — the standard evolutionary process most living things follow. Scientists think this rule-breaking approach may be a reason why octopuses evolve so slowly, and why they are one of the brainiest beasties in the ocean.

But lets face it. Despite all their tricks, octopuses are still working from a snail blueprint, and there’s only so much you can do with that toolbox. They are also highly constrained by their very short lifespan.

So, the first item on an evil octopus to-do list for taking over the world is to live well beyond your first birthday. Second on the list might be to develop “cumulative culture” by learning from others like humans do. We already know an octopus can learn by watching other octopuses, but as yet we don’t have evidence of culture.

Very few creatures display intelligence comparable to humans and understanding why is a long-standing scientific question. The most likely explanation is that brain tissue is extremely expensive to maintain, in terms of energy required to keep brain cells firing. So there need to be big benefits to justify the expense.

Scientists think one benefit of having a big brain is so humans can keep track of complex social relationships (octopuses, on the other hand, are soliltary) and develop culture. Nature tends to provide animals with just enough smarts to get by, and nothing more.

They might do OK in space

It’s hard to imagine an octopus ever-evolving to take over the land. Octopus have no hard parts other than their beak. So while they can move on land, with no bones to hold them up against gravity, they really struggle.

They also have gills which need water to pass over them to breathe. Strangely, they can also “breathe” using their skin. When resting, about 40% of their oxygen comes from the water passing over their skin rather than their gills. Trouble is that only works while the skin is wet.

But because they live in water and octopuses are neutrally buoyant (they neither float nor sink), gravity is largely irrelevant. This means they would do rather well in space where there’s no gravity — assuming they could take water with them.

In short, octopuses are very intelligent animals and one of the smartest creatures in the ocean. But their short life span and vulnerabilities on land are serious handicaps when it comes to taking over the world.

We, for one, welcome any new cephalopod overlords.

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Scientists get more great looks at the 1st black hole ever photographed

Observations of M87’s monster black hole continue to roll in.

The region around the supermassive black hole at the center of the M87 galaxy, as seen in radio, visible and X-ray wavelengths by the ALMA telescope array and NASA’s Hubble and Chandra space telescopes, respectively.

The supermassive black hole at the heart of the galaxy M87 is coming into sharper and sharper focus.

Two years ago, astronomers with the Event Horizon Telescope (EHT) project unveiled imagery of that black hole, which lies 55 million light-years from Earth and is as massive as 6.5 billion suns. Those photos were historic — the first direct views of a black hole that humanity had ever captured.

In the spring of 2017, as the EHT team was gathering some of the data that would result in the epic imagery, nearly 20 other powerful telescopes on the ground and in space were studying the M87 black hole as well.

A new study describes this huge and powerful data set, which contains observations across a wide range of wavelengths gathered by NASA’s Hubble Space Telescope, Chandra X-ray Observatory, the Neil Gehrels Swift Observatory, the Nuclear Spectroscopic Telescope Array (NuSTAR) and Fermi Gamma-ray Space Telescope, as well as a number of other scopes.

“We knew that the first direct image of a black hole would be groundbreaking,” study co-author Kazuhiro Hada, of the National Astronomical Observatory of Japan, said in a statement. “But to get the most out of this remarkable image, we need to know everything we can about the black hole’s behavior at that time by observing over the entire electromagnetic spectrum.”

That behavior includes the launching of jets, or beams of radiation and fast-moving particles rocketing outward from M87’s black hole. Astronomers think such jets are the source of the highest-energy cosmic rays, particles that zoom through the universe at nearly the speed of light.

The new data set gathers the results of the most intensive simultaneous observing campaign ever undertaken on a black hole with jets, study team members said. So, plumbing it could yield key insights into jet dynamics and the origins of cosmic rays, among other things.

“Understanding the particle acceleration is really central to our understanding of both the EHT image as well as the jets, in all their ‘colors,'” co-author Sera Markoff, an astrophysicist with the University of Amsterdam, said in the same statement.

“These jets manage to transport energy released by the black hole out to scales larger than the host galaxy, like a huge power cord,” Markoff said. “Our results will help us calculate the amount of power carried and the effect the black hole’s jets have on its environment.”

M87’s core in a variety of wavelengths.

The EHT, which links radio telescopes around the world to form a virtual instrument the size of Earth itself, is scheduled to begin observing the M87 black hole again this week after a two-year hiatus. The project gathers data only during a short window in the Northern Hemisphere spring each year, when the weather tends to be good at its various observing sites. Technical issues scuttled the 2019 campaign, and last year’s was called off because of the coronavirus pandemic.

As in previous years, the new EHT campaign will also include observations of the supermassive black hole at the heart of our own Milky Way galaxy, a 4.3-million-solar-mass object known as Sagittarius A*. The new data could be even more revealing, because the EHT recently added three big scopes to its network — the Greenland Telescope, the Kitt Peak 12-meter Telescope in Arizona, and the Northern Extended Millimeter Array in France.

“With the release of these data, combined with the resumption of observing and an improved EHT, we know many exciting new results are on the horizon,” study co-author Mislav Baloković, of Yale University, said in the same statement.

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Todd

Galaxies, the cosmic cities of the universe, explained by astrophysicist

Galaxies come in three flavors.

The spiral galaxy M81 is located about 12 million light-years away from Earth.

Galaxies are glittering cities, massive metropolises full of stars, dust, gas, black holes, magnetic fields, cosmic rays, dark matter and more. Separated by millions of light-years of essentially nothing, galaxies are incredibly isolated, each one an island.

Astronomers have identified three kinds of galaxies: spirals, ellipticals and irregulars, and the differences between those kinds of galaxies reveal their complicated histories.

The beautiful

If you were to leave a galaxy largely left alone, subject only to the occasional minor merger (or more accurately, consumption) of a dwarf galaxy, it would naturally develop a set of beautiful spiral arms.

Those spiral arms are created by waves of density rippling across the disk of the galaxy, spinning and overlapping on themselves. These waves stem from sources like nearby passing galaxies, the occasional galactic snack and even chains of supernova explosions.

Despite the bold appearance of spiral arms, these structures aren’t much more dense than galactic average, only by about 10% or so. But that slightly higher density causes a stellar traffic jam, igniting the formation of new batches of stars. Essentially, spiral arms are the sites of active star formation within spiral galaxies.

In star-forming regions, all sorts of stars can form. Big, bright, blue ones. Medium white ones. Small, dim, red ones. But from millions of light-years away, our eyes and our telescopes pick out the bright ones most readily, making the arms visually stand out much more than their density alone would result in.

The boring

The key to beautiful spiral arms in a galaxy is the occasional gravitational encounter or disturbance — emphasis on the word “occasional.” If a galaxy suffers too many collisions or just one big one the turbulence can permanently disfigure a galaxy, forever robbing it of the chance at beauty.

The problem is the merger event itself. When galaxies collide, the stars themselves don’t actually smack into each other — there’s way too much empty space for that to happen. But all those extra gravitational interactions, plus a healthy dose of gas clouds passing too close to each other, set off a round of high-intensity star formation. In the middle of a merger event, which can take hundreds of millions of years to complete, the star formation rate can skyrocket to tens or even hundreds of times higher than normal.

The elliptical galaxy NGC 3610 is surrounded by a host of other galaxies of varying shapes.

For a while, everything is spectacular. Ablaze with freshly-minted stars, the galaxy shines more brightly than it ever has before. Alas, it won’t last. All those new stars come with a price tag: by using up so much star-making material so quickly, the post-merger galaxy stops making stars sooner. In only a few short hundred million years, all the massive stars formed during the merger event die and fade away, with no new stars to replace them.

The result is a giant clump of dim, red stars. The once-beautiful spiral arms are in tatters and the galaxy misshapen. With enough time, the now-giant galaxy settles into an elliptical shape, but despite its grand size remains relatively dim, clinging onto a sad and broken existence for billions of years to come.

The ugly

While most of the galaxies in our universe are either beautiful, grand spirals or giant, boring ellipticals, there are plenty of oddballs. Some galaxies appear to be stretched and distorted like we’re viewing them in a funhouse mirror. Some galaxies appear to have holes blasted right through their centers. Some are just tangled, mangled wrecks, barely discernible as any sort of structure at all.

The culprit behind these oddballs is gravity. The gravitational influence of the galaxies on each other twists and distorts the pair, drawing huge tails of gas, dust and stars out of each galaxy like unraveling a spiral. For a few hundred million years, these two galaxies will look highly irregular.

Smaller collisions can make for some interesting galaxies too. For example, some galaxies look like they’ve gotten cored after a neighboring galaxy plowed through its center, clearing a path through the stars.

The irregular dwarf galaxy NGC 1140 is located about 60 million light-years away in the constellation Eridanus.

Irregular galaxies do usually host ongoing star formation, precisely because whatever influence distorted the galaxy created dense bulges and knots where enough material can condense to form stars.

This makes irregulars some of the most intriguing galaxies out there — no two are alike, but they’re all disturbingly beautiful.

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Rocket, Todd

These 3 spinning brown dwarfs are the fastest ‘failed stars’ ever seen

Astronomers have identified three brown dwarfs spinning faster than any others measured.

The fastest-spinning brown dwarfs ever found may point to a cosmic speed limit.

Brown dwarfs, which are sometimes called “failed stars,” are more massive than most planets but not heavy enough to ignite like stars. Using data from NASA’s Spitzer Space Telescope, scientists have identified three brown dwarfs that are spinning faster than any other found thus far, at one rotation per hour, according to a NASA statement. In a new study, astronomers concluded that these three rapidly-spinning brown dwarfs may be approaching a speed limit for all brown dwarfs.

All three brown dwarfs were discovered by a ground-based program that ended in 2001 called the Two Micron All Sky Survey, or 2MASS. In the new research, scientists used data from the now-retired Spitzer Space Telescope and telescopes operating on the ground. All three brown dwarfs are roughly the size of Jupiter and rotate once per hour, according to the new analysis, meaning that they spin at more than 60 miles per second (100 kilometers per second), or 220,000 mph (360,000 kph).

Scientists have identified three brown dwarfs that are spinning faster than any other measured.

The three brown dwarfs are different temperatures, adding more evidence to the idea of a speed limit, according to the NASA statement. Brown dwarfs are spinning when they form (just like stars or planets), and as they age, cool down and contract they spin faster — much like ice skaters spin faster when they pull their arms into their bodies, the NASA statement explains. Yet, the three brown dwarfs studied in the paper are different ages, which we know because one is cold, one is warm, and one is in-between.

The new research suggests that, because the three worlds are different temperatures, they’re likely approaching a speed limit beyond which brown dwarfs would break apart, flinging their contents out into space due to an overload of centrifugal force. In other astronomical objects, like stars, scientists have found similar natural “braking mechanisms” to prevent spinning too fast and bursting, according to the NASA statement.

Scientists don’t yet know whether brown dwarfs have similar braking mechanisms, but the study authors suggest that the fact that all three of these brown dwarfs are spinning at one rotation per hour hints at such a mechanism.

“It would be pretty spectacular to find a brown dwarf rotating so fast it is tossing its atmosphere out into space,” Megan Tannock, a Ph.D. candidate at Western University in London, Ontario, and lead author on the new study, said in the NASA statement. “But so far, we haven’t found such a thing.”

The three brown dwarfs studied are roughly the size of Jupiter, but between 40 and 70 times more massive.

That absence suggests that either something is slowing the brown dwarfs down or they just can’t get that fast, she said.

As scientists look into whether brown dwarfs have a speed limit, it will become important to understand the interior of these astronomical objects. The maximum spin rate of any object depends not only on its mass, but how that mass is distributed, according to NASA. As a brown dwarf spins faster and faster, the material inside likely shifts and deforms, just as scientists have seen in some planets — Saturn, for example, has a perceptible bulge around the middle, called oblation. The paper authors believe brown dwarfs will have similar degrees of oblation.

Current models of how brown dwarfs should behave, based on what scientists know or suspect about their interiors, predict that the maximum brown dwarf speed should be about 50% to 80% faster than the one-hour rotation of these three.

More observation is needed to determine whether the brown dwarfs described in the paper have hit a limit at which their spinning stops accelerating or if there are brown dwarfs spinning still faster out there, waiting to be discovered.

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Rocket, Todd

5 twinkling galaxies help us uncover the mystery of the Milky Way’s missing matter

We’ve all looked up at night and admired the brightly shining stars. Beyond making a gorgeous spectacle, measuring that light helps us learn about matter in our galaxy, the Milky Way.

When astronomers add up all the ordinary matter detectable around us (such as in galaxies, stars and planets), they find only half the amount expected to exist, based on predictions. This normal matter is “baryonic,” which means it’s made up of baryon particles such as protons and neutrons.

But about half of this matter in our galaxy is too dark to be detected by even the most powerful telescopes. It takes the form of cold, dark clumps of gas. In this dark gas is the Milky Way’s “missing” baryonic matter.

In a paper published in the Monthly Notices of the Royal Astronomical Society, we detail the discovery of five twinkling far-away galaxies that point to the presence of an unusually shaped gas cloud in the Milky Way. We think this cloud may be linked to the missing matter.

Finding what we can’t see

Stars twinkle because of turbulence in our atmosphere. When their light reaches Earth, it gets bent as it bounces through different layers of the atmosphere.

Rarely, galaxies can twinkle too, due to the turbulence of gas in the Milky Way. We see this twinkling because of the luminous cores of distant galaxies named “quasars.”

Astronomers can use quasars a bit like backlights, to reveal the presence of clumps of gas around us that would otherwise be impossible to see. The challenge, however, is that it is very rare to catch quasars twinkling.

This is where the Australian Square Kilometre Array Pathfinder (ASKAP) comes in. This highly sensitive telescope can view an area about the size of the Southern Cross and detect tens of thousands of distant galaxies, including quasars, in a single observation.

Using ASKAP, we looked at the same patch of sky seven times. Of the 30,000 galaxies we could see, six were twinkling strongly. Surprisingly, five of these were arranged in a long, thin straight line.

Analysis showed we’d captured an invisible clump of gas between us and the galaxies. As light from the galaxies passed through the gas cloud, they appeared to twinkle.

At the center is one of the strongly twinkling galaxies. The colors represent brightness, as it fluctuates between shining brightly (red) and more faintly (blue).

A clump of gas ten light years away

The cloud of gas we detected was inside the Milky Way, about 10 light-years away from Earth. For reference, one light-year is 9.7 trillion kilometers.

That means light from those twinkling galaxies traveled billions of light-years towards Earth, only to be disrupted by the cloud during the last ten years of its journey.

By observing the sky positions of not just the five twinkling galaxies, but also tens of thousands of non-twinkling ones, we were able to draw a boundary around the gas cloud.

We were intrigued by the sky positions of the twinkling galaxies in our ASKAP observations. Each black dot above represents a brightly-shining, distant object.

We found it was very straight, the same length as four moons side-by-side, and only two “arcminutes” in width. This is so thin it’s the equivalent of looking at a strand of hair held at arm’s length.

This is the first time astronomers have been able to calculate the geometry and physical properties of a gas cloud in this way. But where did it come from? And what gave it such an unusual shape?

It’s freezing out there

Astronomers have predicted that when a star passes too close to a black hole, the extreme forces from the black hole will pull it apart, resulting in a long, thin gas stream.

But there are no massive black holes near that cloud of gas — the closest one we know about is more than 1,000 light-years from Earth.

So we propose another theory: that a hydrogen “snow cloud” was disrupted and stretched out by gravitational forces from a nearby star, turning into a long thin gas cloud.

Snow clouds have only been studied as theoretical possibilities and are almost impossible to detect. But they would be so cold that droplets of hydrogen gas within them could freeze solid.

Some astronomers believe snow clouds make up part of the missing matter in the Milky Way.

It’s incredibly exciting for us to have measured an invisible clump of gas in such detail, using the ASKAP telescope. In the future we plan to repeat our experiment on a much larger scale and hopefully create a “cloud map” of the Milky Way.

We’ll then be able to work out how many other gas clouds are out there, how they’re distributed and what role they might have played in the evolution of the Milky Way.

Read more: Half the matter in the universe was missing – we found it hiding in the cosmos

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Todd

One of Earth’s nearest stars may be a dark matter factory

A hunt for hypothetical axions streaming from Betelgeuse turns up empty but helps physicists set constraints on their properties

A visual illustration of Betelgeuse’s mysterious dimming. A new study suggests it could be a good candidate for finding axions.

Deep in its searing hot belly, the giant red star Betelgeuse could be producing tons of hypothetical dark matter particles called axions that, if they exist, would give off a telltale signal. A recent search for such a tantalizing emission has turned up empty, but helps physicists place new limits on the putative axion’s properties.

Appearing as a bright red dot in the constellation Orion, Betelgeuse is a well-studied star. It is cosmologically close, being only 520 light-years from Earth, and made headlines last year when it started mysteriously dimming, leading some researchers to believe it could be preparing to explode as a supernova.

Because it is such a large and hot star, Betelgeuse might also be a perfect place to find axions, scientists say. These conjectured particles could have perhaps a millionth or even a billionth the mass of an electron and are ideal candidates to make up dark matter, the mysterious substance vastly outweighing ordinary matter in the universe but whose nature is still largely undetermined.

As dark matter, axions shouldn’t interact much with luminous particles, but according to some theories, there is a small probability that photons, or light particles, could convert back and forth into axions in the presence of a strong magnetic field, Mengjiao Xiao, a physicist at the Massachusetts Institute of Technology (MIT) in Cambridge, told Live Science.

The thermonuclear core of a star is a good place to find copious amounts of both photons and magnetism, and Betelgeuse, which has 20 times the mass of the sun, could conceivably be “what we call an axion factory,” he said.

If axions are produced in this extreme environment, they should be able to escape outwards and stream towards Earth in large numbers. By interacting with the Milky Way galaxy’s natural magnetic field, these axions could be converted back into photons in the X-ray part of the electromagnetic spectrum, Xiao said.

As an elderly star, Betelgeuse is in a life stage where it shouldn’t be emitting much X-ray light, he added, so any such radiation detected from it might indicate the presence of axions.

Xiao and his colleagues used NASA’s space-based Nuclear Spectroscopic Telescope Array (NuSTAR) to hunt for an X-ray signature coming from Betelgeuse, though they saw nothing beyond what was expected from ordinary astrophysical processes such as the small amount of X-rays that Betegeuse is making. Their findings, which Xiao will present on April 20 at the American Physical Society’s April meeting, suggest that photons and axions are at least three times less likely to interact than previously believed.

Because stellar environments are much noisier than conditions found in a lab, doing searches such as this are tricky, said Joshua Foster, a physicist at MIT who was not involved in the work but who has been part of an effort to look for axions coming from the star clusters near our galaxy’s center. But the team worked hard to quantify their uncertainties and helped put new constraints on the axion’s potential properties, Foster told Live Science.

Even if researchers saw unexpected X-rays coming from a star, it wouldn’t necessarily indicate that axions are real. Scientists would still have to rule out many non-dark-matter explanations for the signal before turning to new physics, Foster said.

But it’s possible that axions, should they one day be found, could help astronomers better understand Betelgeuse, Xiao said. If the particles’ properties were known, telescopes trained on Betelgeuse might be able to finally pick up their signal, giving insights into processes happening in its belly and enabling researchers to calculate when it will actually explode, he added.

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Todd

Tiny newfound ‘Unicorn’ is closest known black hole to Earth

‘The Unicorn’ lies a mere 1,500 light-years from us and is just three times more massive than the sun

Artist’s illustration of the tiny black hole candidate known as “The Unicorn” tugging on its companion, a red giant star.

Astronomers have apparently found the closest known black hole to Earth, a weirdly tiny object dubbed “The Unicorn” that lurks just 1,500 light-years from us.

The nickname has a double meaning. Not only does the black hole candidate reside in the constellation Monoceros (“the unicorn”), its incredibly low mass — about three times that of the sun — makes it nearly one of a kind.

“Because the system is so unique and so weird, you know, it definitely warranted the nickname of ‘The Unicorn,'” discovery team leader Tharindu Jayasinghe, an astronomy Ph.D. student at The Ohio State University, said in a new video the school made to explain the find.

“The Unicorn” has a companion — a bloated red giant star that’s nearing the end of its life. (Our sun will swell up as a red giant in about five billion years.) That companion has been observed by a variety of instruments over the years, including the All Sky Automated Survey and NASA’s Transiting Exoplanet Survey Satellite.

Jayasinghe and his colleagues analyzed that big dataset and noticed something interesting: The red giant’s light shifts in intensity periodically, suggesting that another object is tugging on the star and changing its shape.

The team determined that the object doing the tugging is likely a black hole — one harboring a mere three solar masses, based on details of the star’s velocity and the light distortion. (For perspective: The supermassive black hole at the heart of our Milky Way galaxy packs about 4.3 million solar masses.)

“Just as the moon’s gravity distorts the Earth’s oceans, causing the seas to bulge toward and away from the moon, producing high tides, so does the black hole distort the star into a football-like shape with one axis longer than the other,” study co-author Todd Thompson, chair of Ohio State’s astronomy department, said in a statement. “The simplest explanation is that it’s a black hole — and in this case, the simplest explanation is the most likely one.”

That explanation, likely though it may be, is not set in stone; “The Unicorn” remains a black hole candidate at the moment.

Very few such super-lightweight black holes are known, because they’re incredibly hard to find. Black holes famously gobble up everything, including light, so astronomers have traditionally detected them by noticing the impact they have on their surroundings (though we did recently get our first direct image of a black hole, thanks to the Event Horizon Telescope). And the smaller the black hole, the smaller the impact.

But efforts to find extremely low-mass black holes have increased significantly in recent years, Thompson said, so we could soon learn much more about these mysterious objects.

“I think the field is pushing toward this, to really map out how many low-mass, how many intermediate-mass and how many high-mass black holes there are, because every time you find one it gives you a clue about which stars collapse, which explode and which are in between,” he said in the statement.

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Todd

Newfound super-Earth has speedy orbit around red dwarf star

It’s the second shortest orbit of any planet around a red dwarf star discovered so far.

Artistic impression of the super-Earth in orbit around the red dwarf star GJ 740.

A newfound exoplanet has been discovered 36 light-years from Earth.

The exoplanet, named GJ 740 b, is three times the mass of Earth and orbits a red dwarf star called GJ 740. Each orbit takes just 2.4 days, making it the second shortest orbit of any planet around a red dwarf star discovered so far.

Compared to our sun, GJ 740 is tiny, with between 0.08 and 0.45 solar masses. It is also far cooler, with estimated surface temperatures between 3,860 and 6,200 degrees Fahrenheit (2,127 to 3,427 degrees Celsius). For context, our sun’s visible surface is approximately 10,000 degrees Fahrenheit (5,500 degrees Celsius).

“The mass and the period suggest a rocky planet, with a radius of around 1.4 Earth radii, which could be confirmed in future observations with the TESS satellite,” lead researcher Borja Toledo Padrón, a doctoral student at the Instituto de Astrofísica de Canarias (IAC), said in a statement, referring to NASA’s Transiting Exoplanet Survey Satellite (TESS).

This duo is of particular importance due to its relative proximity to Earth. As such, the pair could find themselves the object of future observations using very large telescopes such as ESA’s recently launched Characterising Exoplanets Satellite (CHEOPS). Such observations could confirm whether the super-Earth is alone in its orbit around GJ 740.

This discovery of the newfound super-Earth was part of the HARPS-N red Dwarf Exoplanet Survey (HADES) which relies on the High Accuracy Radial Velocity Planet Searcher for the Northern Hemisphere (HARPS-N) instruments, part of the Galileo National Telescope (TNG) at the IAC’s Roque de Los Muchachos Observatory, Spain. In total, researchers sifted through 11 years’ worth of data to be able to identify the new super-Earth orbiting GJ 740.

In recent years, the search for exoplanets has been gaining momentum, building upon findings from NASA’s Kepler Space Telescope and TESS missions.

Cooler stars like GJ 740 make particularly good hunting grounds for new planets, as scientists predict each of these stars has on average 2.5 planets in orbits of less than 200 days. These predictions were based on data collected during the Kepler mission, regarded as one of the most successful exoplanet-hunting missions to date.

NASA’s Kepler Space Telescope operated for just under nine years until its decommissioning in 2018. As of November 2020, Kepler had been credited with discovering 2,392 confirmed exoplanets. Of those worlds, 156 are located around cool stars and were discovered using the transit method, which involves searching for tiny dips in the brightness of a star caused by a planet passing in front of it.

Artistic impression of Kepler-62f, a super-Earth located about 1,200 light-years from Earth.

But the transit method is not the only way to find exoplanets orbiting distant stars. In this study, researchers employed the radial velocity method, which involves measuring the small variations in the velocity of a star that are driven by the gravitational tugs of an orbiting planet.

According to NASA, a total of 837 planets have been discovered using the radial velocity method, so far, making up almost 20% of all exoplanet discoveries. Of these findings, 116 of the exoplanets reside around red dwarf stars. Though highly effective, there are however some drawbacks to such a method.

“The main difficulty of this method is related to the intense magnetic activity of this type of stars, which can produce spectroscopic signals very similar to those due to an exoplanet,” co-author Jonay I. González Hernández said in the same statement.

The researchers said their work also suggests the presence of a second planet approximately the size of Saturn that orbits GJ 740 every nine years. However, that radial velocity signal could have been caused by the magnetic cycle of the star, so the scientists are cautious and hope to gather more data.

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Todd

‘Exotic compact objects’ could soon break physics, new study suggests

Gravitational wave detectors could soon uncover hints of new physics from exotic compact objects.

LIGO was built to detect ripples in space-time as massive objects like black holes crash into each other.

Out in the depths of the universe, outlandish black-hole-like entities might exist with the power to redefine physics as we know it. A new study calculates that, in the coming years, gravitational wave observatories on Earth could find these hypothetical oddballs, which are known as exotic compact objects.

The U.S.-based Laser Interferometer Gravitational-Wave Observatory (LIGO) and its European counterpart Virgo were built to capture ripples in the fabric of space-time radiating from massive objects like black holes and neutron stars crashing together. Yet there is always the chance that scientists could run into something unexpected.

“We can’t be so naïve to presume that we know everything that is out there,” Luís Longo, a doctoral candidate in physics at the Universidade Federal do ABC in São Paulo, Brazil, told Live Science.

Researchers have been speculating about the possibilities of exotic compact objects for many years, and trying to determine what they would look like to a gravitational wave detector, Longo added.

The term “exotic compact object” encompasses a variety of different theoretical entities. Among the possibilities are gravastars, which would appear quite similar to an ordinary black hole but would be filled with dark energy, a mysterious substance causing the accelerated expansion of the universe. Another compact object that could lurk in the universe is a fuzzball, a black-hole-like knot of fundamental one-dimensional strings proposed in string theory, which attempts to unify and replace the current accepted theories in physics.

The thing that connects exotic compact objects is that, unlike a black hole, they should lack a region known as an event horizon, Longo said. According to Albert Einstein’s theory of relativity, the event horizon is a sphere surrounding a black hole beyond which any trip becomes one-way. Objects can slip inside the event horizon but nothing can come out of it — not even light.

But scientists know that Einstein’s theory of relativity will one day have to be replaced. Though the theory is extraordinarily successful at describing gravity and massive cosmic entities, it says nothing about the behavior of subatomic particles. For that, physicists turn to quantum mechanics.

The hope is to eventually have a theory of quantum gravity that supersedes both relativity and quantum mechanics. Exotic compact objects, which would be like a black hole but lack an event horizon, could help provide the necessary information to start constructing this future theory.

“They will break with general relativity because they won’t give rise to one of its key predictions,” Longo said, referring to the event horizon. “In this sense we would be testing Einstein’s theory of gravitation.”

As two black holes crash and merge, they spin around one another, warping space-time and sending out gravitational waves, which can ring LIGO’s detectors on Earth. After they meet, the event horizon prevents additional waves from escaping outward, Longo said.

But because exotic compact objects would lack an event horizon, some gravitational waves could fall inward towards the object’s center and then bounce back, creating gravitational echoes that leak outward, he added. These echoes are too faint for LIGO and Virgo to detect right now, but the facilities are currently being upgraded for increased sensitivity, and they’ve been joined by the Kamioka Gravitational Wave Detector (KAGRA) in Japan, which became operational last year.

Longo and his colleagues have calculated that during the gravitational wave detectors’ next observation run, set to begin in the summer of 2022, LIGO and its counterparts could be sensitive enough to pick up the signal from one or two exotic compact objects, if they exist. Longo will present his team’s findings at the American Physical Society’s April meeting on April 19.

Other researchers are keen to see if such a scenario might play out in the near future. “Right now, it looks like science fiction,” Vitor Cardoso, a physicist at the Instituto Superior Técnico in Lisbon, Portugal, who was not involved in the work, told Live Science. “But it quickly goes from science fiction to established science.”

Cardoso would be thrilled if exotic compact objects turned out to be more than speculation. “We hate seeing what we expect,” Cardoso said. “We hate boring science.”

However, even if LIGO detected echoes, it would still likely take a long time before the scientific community confirmed that they were really pointing to these hypothetical oddballs, he added.

Longo, too, would be happy if the observatories managed to uncover some evidence for exotic compact objects. “It would be the first hint of the breakdown of general relativity,” he said. “It would be an enormous breakthrough and extremely exciting.”

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Todd