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Moons are the norm in our Solar System. The International Astronomical Union recognizes 288 planetary moons, and more keep being discovered. Saturn has a whopping 146 moons. Every planet except Mercury and Venus has moons, and their lack of moons is attributed to their small size and proximity to the Sun.

It seems reasonable that there are moons around exoplanets in other Solar Systems, and now we’re going to start looking for them with the James Webb Space Telescope.

The Cool Worlds Lab is part of the Columbia University Astronomy Department and is led by assistant professor David Kipping, a well-known British/American astronomer. The Lab focuses on cool exoplanets with wide orbits around stars. “In this regime, orbital dynamics and atmospheric chemistry diverge from their hot counterparts, and the potential for satellites, rings, and habitability become enhanced,” the Lab’s website says. Exomoons around these planets are part of the Lab’s focus, and Kipping is an author and co-author of several papers about exomoons.

There’s a lot of active discussion in the astronomy world about exomoons, how to find them, and how to confirm them. Currently, there are no confirmed exomoons, only a list of candidates, some of which should be in habitable zones if they’re real.

Kipping and his team have succeeded in getting some JWST observation time to look for an exomoon. Back in February, his proposal was selected. “We have been hoping to find exomoons for a very long time,” Kipping says in a YouTube video announcing the beginning of their JWST observations, adding that exomoons have been “a continuous thread in my career.”

Now, Kipping and the Cool Worlds Lab is being given a chance to use the world’s most powerful space telescope to observe an exoplanet named Kepler-167e. Kipping himself found this planet about 10 years ago, and there’s something special about it. It’s a Jupiter analogue and a very rare example of a long-period transiting gas giant. Because Jupiter has so many moons, Kipping and others argue that Kepler-167e is a strong candidate to also have moons.

An artist’s illustration of Kepler-167e, a Jupiter analogue in a distant solar system. At the time of writing, the JWST is observing this planet and looking for signs of an exomoon. Image Credit: NASA Eyes On Planets

The planet only transits its star once every three years, and the next transit is happening right now. In fact, it started yesterday morning, and the JWST was watching on behalf of the Cool Worlds Lab. The JWST has given the Lab 60 hours—2 and a half days— of observing time. Those observations are happening right now, and if all goes well, we may have our first strong detection of an exomoon.

The data from these observations is exclusive to the Cool Worlds Lab for one year. “We have a year before the data goes public, and that’s fairly normal with JWST data,” Kipping said.

Kipping says they have to be cautious when they get their initial results. “I’ve been in this situation many times. You get the data on the first day. You see a dip and you’re like ‘That’s it. We’re there. We’ve got a moon.’ ” But a few weeks or months later, it could turn out to not be real. “So we don’t want to get people’s excitement up prematurely,” he said.

Looking for exomoons is extremely challenging and Kipping led an effort to find some in Kepler’s data. “We surveyed probably on the order of 300 or 350 exoplanets during our time, and only two real candidates popped up over this entire analysis,” Kipping said in an interview with Fraser Cain earlier this year. One of the candidates was Kepler-1625 b, and even then, they only had the “smallest of hints from the Kepler data that there was something there,” he said.

In 2018, researchers presented evidence in support of an exomoon orbiting Kepler-1625b, a super Jupiter 8,200 light-years away. Subsequent research poured cold water on the moon’s existence. Image Credit: By ESA/Hubble, CC BY 4.0, https://commons.wikimedia.org/w/index.php?curid=73369715

Kipping told Universe Today that “we’re really pushing these data sets to their limits to even get these signals.”

But the JWST’s data should be more robust than Kepler’s. Kepler was an automated survey, while the JWST is a different beast. Kepler had a fixed field of view and a primary mirror only 0.95 meters in diameter. Its sole job was to detect exoplanets that transited in front of their stars. The JWST has a 6.5-meter mirror, multiple instruments, including cameras and spectrographs, and a system of filters. It’s far more capable than Kepler, as almost everyone knows.

Kipping is hopeful that the JWST will be able to detect moons as small as Ganymede and Callisto. There’s a chance that the JWST will detect a slam-dunk exomoon and that it’ll be clear to everyone. “That’s the dream scenario,” Kipping says. However, this set of observations will be scientifically rich whether they detect an exomoon or not because the JWST will be able to measure other things about the planet.

“But there’s also a scenario where we don’t see anything,” Kipping said. If that happens, it would also be a significant finding. “We would essentially have to rip up the textbook,” Kipping said. “If we don’t see a Titan, if we don’t see a Ganymede, we don’t see a Callisto, that is telling us something quite profound about Moon formation, maybe that our Solar System’s kind of special.”

Enhanced image of Ganymede taken by the JunoCam during the mission’s flyby on June 7th, 2021. Ganymede is our Solar System’s largest moon and potentially holds a subsurface ocean. Ganymede and other moons in our Solar System are suspected of having warm, potentially life-supporting oceans under layers of ice. It seems highly likely that some exomoons will also have oceans and be potentially habitable. Image Credit: NASA/JPL-Caltech/SwRI/MSSS/Kalleheikki Kannisto

This mirrors what we used to say about exoplanets. Prior to the Kepler mission, which found over 2,500 exoplanets, we weren’t certain if our Solar System’s planet population was normal or extraordinary. Now we know that exoplanets are likely orbiting every star. (Though our Solar System is still special.)

We may be on the verge of an age of exomoon discovery, just as we were prior to Kepler’s launch. The Cool Worlds Lab exomoon observations are just one of five exomoon observing efforts the JWST has approved, and the JWST isn’t the only telescope that will be searching for them. The ESA’s upcoming PLATO (PLAnetary Transits and Oscillations of stars) mission will study exoplanets in habitable zones around Sun-like stars, and it will also discover exomoons.

Kipping is boiling over with enthusiasm about the JWST’s observations of Kepler-167e. He discovered the planet, and if he and his team were able to find the first confirmed exomoon around it, it would be quite an achievement.

“It’s an amazing opportunity that we have to potentially test some long-standing theories,” Kipping said, adding that it’s also a “dream I’ve had for my entire career.”

For updates on the observations, follow Cool Worlds on YouTube.

The post The Search for Exomoons is On appeared first on Universe Today.

Large language models can be used to scam humans, but AI is also susceptible to being scammed – and some models are more gullible than others

This is strange given the paper’s political leanings and the fact that it’s endorsed candidates for 48 years running, but this morning the Washington Post declared that it will not be endorsing a candidate in this year’s political elections, or ever again. Click on the headline below to see the statement of the paper’s publisher and chief executive officer, or find the article archived here.

Excerpts:

The Washington Post will not be making an endorsement of a presidential candidate in this election. Nor in any future presidential election. We are returning to our roots of not endorsing presidential candidates.

This is not the first time the paper demurred, but it now sets a precedent for all future Presidential elections:

As our Editorial Board wrote in 1960:

“The Washington Post has not ‘endorsed’ either candidate in the presidential campaign. That is in our tradition and accords with our action in five of the last six elections. The unusual circumstances of the 1952 election led us to make an exception when we endorsed General Eisenhower prior to the nominating conventions and reiterated our endorsement during the campaign. In the light of hindsight we retain the view that the arguments for his nomination and election were compelling. But hindsight also has convinced us that it might have been wiser for an independent newspaper in the Nation’s Capital to have avoided formal endorsement.”

Indeed, but the paper’s slant towards Kamala Harris was so palpably obvious that they might as well have endorsed her!

More:

And again in 1972, the Editorial Board posed, and then answered this critical question ahead of an election which President Richard M. Nixon won: “In talking about the choice of a President of the United States, what is a newspaper’s proper role? … Our own answer is that we are, as our masthead proclaims, an independent newspaper, and that with one exception (our support of President Eisenhower in 1952), it has not been our tradition to bestow formal endorsement upon presidential candidates. We can think of no reason to depart from that tradition this year.”

That was strong reasoning, but in 1976 for understandable reasons at the time, we changed this long-standing policy and endorsed Jimmy Carter as president. But we had it right before that, and this is what we are going back to.

. . . We recognize that this will be read in a range of ways, including as a tacit endorsement of one candidate, or as a condemnation of another, or as an abdication of responsibility. That is inevitable. We don’t see it that way. We see it as consistent with the values The Post has always stood for and what we hope for in a leader: character and courage in service to the American ethic, veneration for the rule of law, and respect for human freedom in all its aspects. We also see it as a statement in support of our readers’ ability to make up their own minds on this, the most consequential of American decisions — whom to vote for as the next president.

Our job at The Washington Post is to provide through the newsroom nonpartisan news for all Americans, and thought-provoking, reported views from our opinion team to help our readers make up their own minds.

Most of all, our job as the newspaper of the capital city of the most important country in the world is to be independent.

In general I agree—if you see the word “independent” as meaning “having no slant on the news or on our official position.”  Having “institutional neutrality” in this way reassures the reader that the news will not be biased one way or another.

But my problem with this is that the Post, even more than the New York Times, has been strongly slanted (in both news and opinion) towards Harris and other Democrats. So why the change? Will we expect to see more unbiased news now, sort of like the Wall Street Journal? Let us hope so, for it’s getting harder and harder to find unbiased examples of “mainstream media.”

The NYT also reported on this (in its business section). Click below to read or find the piece archived here.

 The Times spreads some rumors:

Questions about whether The Post would endorse a candidate this year have spread for days. Some people have speculated, without any proof, that the paper’s billionaire owner, Jeff Bezos, was being cowed by a prospective Trump administration because his other businesses have many federal government contracts.

Mr. Lewis, in his note to the staff, said little about how The Post arrived at its decision, adding only that it was not “a tacit endorsement of one candidate, or as a condemnation of another.” He referenced an editorial the paper published in 1960 that it was “wiser for an independent newspaper in the Nation’s Capital” to avoid an endorsement.

The Washington Post’s editorial writers had already drafted an endorsement of Vice President Kamala Harris for president, according to four people who spoke on condition of anonymity to discuss sensitive newsroom matters.

. . . . The Post’s editorial board had contacted the Harris campaign and the Trump campaign to request interviews ahead of its decision to endorse, two of the people said. Ms. Harris declined the interview and the Trump campaign didn’t respond, one of the people said.

The Post’s decision drew immediate blowback on social media, including from Marty Baron, the recent editor of The Post who led the paper through a period of editorial and business success.

“This is cowardice, with democracy as its casualty,” Mr. Baron said in a post on X. He added that former President Donald J. Trump would see it as an invitation to continue to try to intimidate Mr. Bezos. “Disturbing spinelessness at an institution famed for courage.”

The Post’s move follows unfurling tumult at The Los Angeles Times, where the head of the editorial board and two of its writers have resigned this week to protest the decision by The Times’s owner, the billionaire Patrick Soon-Shiong, to block a planned presidential endorsement.

Upset, several Post editorial board members resigned, as they thought the paper should endorse Harris. But note that the editorial board itself had already endorsed Harris:

Newspapers across the United States have steadily backed away from endorsing political candidates in recent years.

The New York Times’s editorial board, which operates separately from the newsroom, endorsed Ms. Harris for president on Sept. 30, saying: “It is hard to imagine a candidate more unworthy to serve as president of the United States than Donald Trump.” But in August, it said it would stop endorsing candidates in New York elections, including the New York City mayoral race.

We’ve accepted these endorsements for years and I, for one, have never questioned them.  But really, what purpose do they serve? Thinking about it, they seem a form of condescension or even compulsion, as if the readers can’t be trusted to make up their minds after reading or hearing the news.

In the end, I think the Post did the right thing, and I think other papers should follow in its wake.  Yes, of course continue to have editorials written by others, ideally representing a variety of views, but an official endorsement by a paper itself makes readers wary of its objectivity when it comes to the news—and reporting the news objectively is, of course, the first duty of a paper.

The great auk (Pinguinus impennis) displayed in the Natural History Museum of Denmark stands erect on its pedestal, its great beak jutting forward, apparently fearless. It is possessed of a certain dignity and grace. It demands my attention. It was probably killed off in Iceland, where I come from, and was one of the last of its kind. For thousands of years, these large, flightless birds swam the extensive waters of the North Atlantic and made their nests on islands and skerries, where each pair laid and incubated a single, uniquely patterned egg per year. According to most accounts, the last of the great auks were slaughtered on Eldey, an island off the southwest coast of Iceland, in June 1844. About eighty taxidermic examples of great auks exist in various museum collections, and most of them came from Eldey.

Alongside the great auk displayed in Copenhagen are four large glass jars. One is labeled: Iceland 1844, . These jars contain the viscera of great auks killed on that famous (or infamous) expedition to Eldey. These are not all the birds’ organs; some are stored in another seven jars elsewhere in the museum, out of the public eye, along with another stuffed great auk. At my request, a museum guide takes me to see this second bird. It is posed somewhat differently than the one on display. Its beak is open, as if ready to address the visitor. Unlike the first bird’s stark black-and-white plumage, this one looks grayish and rather dull. I am told it is a true rarity; it is in winter plumage, while most great auks were captured while breeding, in early summer. Perhaps this second bird was caged alive and slaughtered in winter. Perhaps it was kept as a pet for some months, like the great auk owned by the Danish polymath Ole Worm (1588–1654), one of the leading figures of the Nordic Renaissance. Worm personally owned three great auks, one of which he sometimes walked on a leash, and he made a fine drawing of it before adding it—stuffed—to his Wunderkammer, or cabinet of curiosities, a precursor to the modern museum.

In its imposing old building in Copenhagen, only a fraction of the Danish museum’s “curiosities” are on display. In full, the collection comprises millions of animals from around the globe, and boasts exemplars of several species that have become extinct in recent centuries—such as a well-preserved skull of a dodo (Raphus cucullatus)—as well as fossils of dinosaurs and other organisms from previous eras of the earth’s history. Here, in this old and venerable museum, it is easy to detect the ideas that lay behind the collecting of natural objects for the past three and a half centuries. The need was perceived to educate the populace of various European nations, whose empires extended around the world, about the progression of time and about their place in the expanding universe. Such collections demonstrated the might and extent of each empire, and the value of research: all things can be named, catalogued, and categorized systematically.

Is such an approach still valid in our current era, now termed the Anthropocene, or Human Age? In our time, the “natural” habitat of the planet has been radically refashioned by humans. Vital links between species, developed over eons, have been severed swiftly, fundamentally impoverishing the living world and posing a serious threat of the mass extinction of many species. How, I wonder, can such a process possibly be cataloged or categorized, given the speed of change and the complexities involved— and what would be the point?

The bird species that no longer exist had, and still have, a special attraction. They have much to teach us.

Extinction

I never saw a great auk growing up in Iceland, a land where they had once been quite common. Neither did the nineteenth-century British naturalists John Wolley and Alfred Newton.

Like their contemporaries, Wolley and Newton busily collected birds’ eggs and specimens, classifying and recording them in the fashion of the Victorian age. When they set off for Iceland in 1858, they hoped to visit Eldey Island and study the rare great auk. They hoped to observe its behavior and habits and, perhaps, bring home an egg, or a skin, or a stuffed bird or two for their own cabinets of curiosities—unaware of the fact that the species had already been hunted to extinction. When they left Victorian England for Iceland, they teased that this was a “genuinely awkward expedition.” And so it proved to be, in many ways. They never made it to Eldey. Like me, they never saw a great auk on Iceland, not even a stuffed one.

Prior to the killing of the last great auks, extinction was either seen as an impossibility or trivialized as a “natural” thing. The great taxonomist Carl von Linné, or Linnaeus (1707–78), imagined that a living species could never disappear; for evolutionary theorist Charles Darwin (1809–82), species would naturally come and go in the long history of life. The great auk brought home the fact that a species could perish quite quickly and, moreover, not naturally, but primarily as a result of human activities. No other extinction had been documented as carefully.

During their historic expedition to Iceland in 1858, Wolley and Newton collected impressions of great auk hunting, through substantial interviews with the men who took part in the latest hunts and the women who skinned and mounted the birds, along with their prices and sales on foreign markets to collectors of “curiosities.” These impressions were preserved in the set of five handwritten notebooks Wolley titled the Gare-Fowl Books. Now archived in Cambridge University Library in England, their hundreds of pages are written in several languages (English, Icelandic, Danish, and German). As an anthropologist and an Icelander, once I had seen the Gare-Fowl Books, there was no turning back: I had to dive into the text and visit zoological museums and archives. For me, the great auk opened an intellectual window into ideas of extinction and their relevance to the current mass disappearance of species.

De-extinction

Many sightings of great auks were reported after 1844 on North Atlantic skerries in Iceland (1846, 1870), Greenland (1859 or 1867), Newfoundland (1852, 1853), and northern Norway (1848). Some of the reports were certainly apocryphal: people had mistaken another species for a great auk, or had seen what they wanted to see. Others were deemed credible and were probably true: evidence of a few dispersed pairs of birds continuing to breed on islands or skerries for a few years. Such tales were often unjustly dismissed, and unnecessarily strict standards of proof and corroboration were applied. The consensus among scholars today seems to be that the last living great auk was seen off Newfoundland in 1852.

Once it seemed clear that the last great auks were dead, museums and collectors around the world scrambled to acquire skins, eggs, and bones of the extinct bird. The Victorian obsession with collecting was past its peak, but anything relating to the great auk remained a prize. There are some eighty stuffed great auks in collections around the world, and an unknown number of preserved skins and viscera. Only about twenty-four complete skeletons exist, while thousands of loose bones (some with knife marks) are kept in museum collections. The skeletons do not have the visual appeal of the stuffed birds, mounted to look so lifelike in their full plumage. However, the bones—what Wolley and Newton termed “relics”—tell a long and complex story of their own. And there are about seventy-five great auk eggs believed to be extant today, the vast majority being documented and numbered.

Now and then over the years, various species have been said to reappear suddenly, after having been thought long exterminated. Several birds have been confirmed to be such so-called “Lazarus species,” including the Bermuda petrel (Pterodroma cahow), which scared Spanish explorers away with their eerie calls. Considered extinct for three centuries, it was rediscovered on one of the Bermuda Islands in 1951. Also, the flightless takahē (Porphyrio hochstetter) of New Zealand, which was claimed extinct late in the nineteenth century, reappeared in 1948. In recent years, with intensive searching, social media, and growing awareness of the threat of mass extinction, such reports have escalated. However, the possibility of any surviving great auk “Lazarus” can be ruled out.

Charles Darwin made the point that species swept away by history would not return. They were gone for good. In On the Origin of Species, he wrote: “We can clearly understand why a species when once lost should never reappear, even if the very same conditions of life, organic and inorganic, should recur.” This has long seemed blindingly obvious. No doubt many people have wondered why Darwin saw reason to state it at all. Yet his words were perhaps necessary at the time. The meaning of extinction had not yet been fixed, and Darwin may well have felt it was time to dispel the fantasy regarding the resurrection of species.

Alfred Newton, on the contrary, entertained the idea that extinction processes could be reversed. And in our own time, discussions of the renaissance, even resurrection, of species is taken for granted—as if Bible stories and the natural sciences had coalesced into one, after centuries of enmity and conflict. Will we live to see the resurrection of Pinguinus impennis? Might genetics and cloning do the trick?

In the spring of 2015, a group of like-minded individuals met at the International Centre for Life in Newcastle, England, to discuss the possible reanimation of the great auk. The meeting was attended by more than twenty people, including scientists and others interested in bird conservation. They addressed the principal stages of “de-extinction,” from the sequencing of the full genome of the extinct animal to the successful releasing of a proxy animal population into the wild. They were interested in resurrecting the great auk quite literally, to see it thrive once more, in zoos or even on the skerries and islands of the North Atlantic.

Thomas Gilbert, a geneticist at the University of Copenhagen who has sequenced the great auk genome was one of the scientists who attended. The de-extinction of a species, however, has proved to be a more complicated issue than was originally anticipated—both technically and ethically. Gilbert pointed out that a re-created species can never be exactly like the original, and that the question must be asked: What counts as “near enough”—ninety-five percent, ninety, …? If the element that is lacking, though it may only account for a few percent of the genome, turns out to be crucial, and makes it harder for a re-created species to survive or to reproduce, nothing will have been gained. A re-created great auk that could not swim, for instance, would not be “near enough.” Likewise, a great auk capable of flight might be “way too much.” For most people, whatever the species concept to which they subscribe—and there remains a thriving philosophical debate on that subject—a flying bird would hardly qualify for legitimate member of the great auk species.

Yet a substitute bird that could swim would be welcomed by many, as it might fill in the large gap left by the great auk’s extinction. A substitute species might contribute to the rewilding of the oceans, a task that has barely begun; indeed “the underwater realm has been trailing behind its terrestrial counterparts.” Interestingly, this idea echoes Philip Henry Gosse’s historic aquaria project, reversing the arrows, from land to sea, and operating on a much larger scale. The grand aquarium of the planet’s oceans, including the recently discovered seabirds’ hotspot in the middle of the North Atlantic, or so the idea goes, could be repopulated by relatively large charismatic animals, territorially raised and later released into the oceans, where they would be managed and monitored by human divers. Gosse would be amused.

The expense of such de-extinction is high, however, and it is hard to decide which species should have priority: the mammoth? the dodo? the great auk? or perhaps one of the numerous species of tiny snails that rarely generate human concern? It’s tempting, and productive, to focus on tall birds and charismatic megafauna, but invertebrates such as snails and insects, which make up most of the animal kingdom (perhaps 99 percent), deserve attention too. In the Anthropocene, this age of mass human-caused extinctions, the selection of species is clearly an urgent, but difficult, concern. The re-creation of the great auk assuredly has symbolic significance, not least in light of the attention the species has garnered from both scholars and the public since its demise. The excessive price nowadays of great auk remains is significant too.

This article appeared in Skeptic magazine 29.3
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In January 2023, a great auk egg sold for $125,000 at Sotheby’s. But bringing the bird back to life is a gigantic challenge, if not an impossible one. Perhaps the funds that would be spent on the de-extinction of the great auk might be better spent elsewhere. Nor should we overlook the Law of Intended Actions, Unintended Consequences.

• • • • • •

Now that I know the great auk’s long history, I feel as if the stuffed birds in the Copenhagen museum were once my neighbors or acquaintances. As a scientist, I know that their viscera are stored in alcohol to preserve them and to enable people to study them. Still I wonder if the organs are in a constant state of inebriation from the alcohol, existing beyond the bounds of real time, in a sort of euphoric oblivion? Generations of visitors, of all ages and many nationalities, have passed by these jars of preserved bird parts over the past century and a half. What observations did they take home?

The hearts stored in one jar are no longer beating, but no doubt many visitors on my side of the glass have wondered, as I do, how they would have pulsed when the bird’s blood was still flowing—and whether they could be resuscitated, by electric shock or genetic reconstruction. The eyes of the last male great auk are kept in another jar. I see them staring, gazing into both the past and into my own eyes.

This essay was excerpted and adapted by the author from The Last of Its Kind: The Search for the Great Auk and the Discovery of Extinction. Copyright © 2024 by Gísli Pálsson. Reprinted by permission of Princeton University Press.

About the Author

Gísli Pálsson is professor emeritus of anthropology at the University of Iceland. He previously held positions in the Department of Anthropology at the University of Oslo, the Centre for Biomedicine & Society at King’s College, London, and at the Rosenstiel School of Marine, Atmospheric, and Earth Science at the University of Miami. His books include The Last of Its Kind: The Search for the Great Auk and the Discovery of Extinction, Down to Earth, and The Man Who Stole Himself.

Remember that amazing “first image” of Sagittarius A* (Sgr A) black hole at the heart of the Milky Way? Well, it may not be completely accurate, according to researchers at the National Astronomical Observatory of Japan (NAOJ). Instead, the accretion disk around Sgr A* may be more elongated, rather than the circular shape we first saw in 2022.

Scientists at NAOJ applied different analysis methods to the data of Sgr A* first taken by the Event Horizon Telescope (EHT) team. The EHT data came from a network of eight ground-based radio telescopes. The original analysis showed a bright ring structure surrounding a dark central region. The re-analysis resulting in a different shape implies something about the motions and distribution of matter in the disk.

In fairness to both teams, radio interferometry data is notoriously complex to analyze. According to NAOJ astronomer Miyoshi Mikato, the rounded appearance may be due to the way the image was constructed. “We hypothesize that the ring image resulted from errors during EHT’s imaging analysis and that part of it was an artifact, rather than the actual astronomical structure,” Miyoshi suggested.

This is the first image of Sgr A*, the supermassive black hole at the center of our galaxy. A reanalysis of EHT data by NAOJ scientists suggests its accretion disk may be more elongated than circular. Credit: EHT Explaining the Black Hole Appearance

So, what does Sgr A* look like in the NAOJ re-analysis? “Our image is slightly elongated in the east-west direction, and the eastern half is brighter than the western half,” said Miyoshi. “We think this appearance means the accretion disk surrounding the black hole is rotating at about 60 percent of the speed of light.”

The accretion disk is filled with superheated material “circling the drain” as it were. It’s funneling into the 4-million-solar-mass black hole. As it cycles through the accretion disk, friction and the action of magnetic fields heat the material. That causes it to glow, mostly in x-rays and visible light as well as giving off radio emissions.

Various factors also influence the shape of the accretion disk, including the spin of the black hole itself. In addition, the accretion rate (that is, how much material falls into the disk), as well as the angular momentum of the material, all affect the shape. The gravitational pull of the black hole also distorts our view of the accretion disk. That sort of “funhouse mirror” distortion makes it incredibly difficult to image. As it turns out, either view of the disk’s actual shape—the original EHT “circular” view or the NAOJ elongated view—could be accurate.

So, Why the Different Views of the Black Hole?

How did the teams come up with two slightly different views of Sgr A* using the same data? “No telescope can capture an astronomical image perfectly,” Miyoshi pointed out. For the EHT observations, it turns out that interferometric data from the widely linked telescopes can have gaps. During data analysis, scientists have to use special techniques to construct a complete image. That’s what the EHT team did, resulting in the “round black hole” image.

Miyoshi’s team published a paper describing their results. In it, they propose that the “ring” structure in the 2022 image released by EHT is an artifact caused by the bumpy point-spread function (PSF) of the EHT data. The PSF describes how an imaging system deals with a point source in the region it’s looking at. It helps give a measure of the amount of blurring that occurs because of imperfections in the optics (or in this case, the gaps in the interferometric data). In other words, it had problems with “filling” in the gaps.

The NAOJ team reanalyzed the data and used a different mapping method to smooth over the gaps in the data. That resulted in an elongated shape for the Sgr A* accretion disk. One-half of the disk is brighter and they suggest it’s due to a Doppler boost as the disk rotates rapidly. They suggest that the newly analyzed data and elongated image shows a portion of the disk that lies a few Schwarzschild radii away from the black hole, rotating extremely fast, and viewed from an angle of 40°-45°.

What’s Next?

This reanalysis should help contribute to a better understanding of what the Sgr A* accretion disk actually looks like. The EHT study of Sgr A* resulting in the 2022 image release was the first detailed attempt to map the region around the black hole. The EHT consortium is working on improvements to produce better and more detailed interferometry images of this and other black holes. Eventually, that should result in more accurate views. Follow-up studies should help fill in any gaps in the observations of the accretion disk. In addition, detailed studies of the near environment around the black hole should give more clues to the black hole hidden inside the disk. I

For More Information

First Picture of Milky Way Black Hole ‘May Not Be Accurate’
An Independent Hybrid Imaging of Sgr A* from the Data in EHT 2017 Observations

The post The Milky Way’s Supermassive Black Hole Photo Might Need a Retake appeared first on Universe Today.

The largest and most ambitious Martian drone yet could carry kilograms of scientific equipment over great distances and set itself down on the Red Planet unassisted

As a megadrought stresses the water supply throughout the Southwest, revolutionary research is answering this problem with a groundbreaking technology that pulls large amounts of water from the air in low humidities.

A new study has revealed that methane gas may be trapped within the icy surface of Saturn's moon Titan, forming a distinct crust up to six miles thick, which warms the underlying ice shell and may also explain Titan's methane-rich atmosphere.

Researchers have developed a groundbreaking new material poised to advance high-sensitivity recyclable sensor technology. The team created a recyclable high-sensitivity sensor based on the dynamic polymer network. This next-generation material is garnering attention for its ability to combine environmental sustainability with high performance.

Researchers have successfully developed an ultra-sensitive pressure sensor for electronic skin modeled after the nervous system in the human brain. This technology is applicable to future devices, including AI-based digital healthcare devices, and is expected to be utilized across various fields, such as transparent displays and wearable devices, due to its transparency and physical flexibility.

Researchers have successfully developed an ultra-sensitive pressure sensor for electronic skin modeled after the nervous system in the human brain. This technology is applicable to future devices, including AI-based digital healthcare devices, and is expected to be utilized across various fields, such as transparent displays and wearable devices, due to its transparency and physical flexibility.

Researchers have significantly improved the performance of kesterite (CZTSSe) thin-film solar cells. They developed a new method for doping silver (Ag) in solar cells to suppress defects that hinder cell performance and promote crystal growth, thereby dramatically increasing efficiency and paving the way for commercialization.

- DGIST, KAIST, and Korea University collaborated to develop a three-dimensional device with reversible heating/cooling based on the thermal radiation phenomenon -- Research published as a cover article in Advanced Materials

Researchers have developed a miniature soft lithium-ion battery that could be used as a defibrillator to control heart rhythm during surgery. The flexible lithium-ion battery is constructed by assembling biocompatible hydrogel droplets. The state-of-the-art device is the smallest soft lithium-ion battery with the highest energy density. The research opens the way to developing tiny bio-integrated devices, with a range of applications in robotics, biology, and medicine.

Researchers have exclusively observed molecules participating in hydrogen bonds in liquid water, measuring electronic and nuclear quantum effects that were previously accessible only via theoretical simulations.

Art and science are sometimes poles apart, but that isn't the case in a new research project. For this work, an interdisciplinary team merged scientific research, technological advancements and artistic exploration to experiment with the production, properties and application of a new kind of ceramic.

A researcher has developed a new technique using light which could revolutionize non-invasive medical diagnostics and optical communication. The research showcases how a type of light called the Orbital Angular Momentum (OAM) can be harnessed to improve imaging and data transmission through skin and other biological tissues.

Climate change-related extreme weather, such as massive flooding and prolonged drought, often result in dangerous outbreaks of diarrheal diseases particularly in less developed countries, where diarrheal diseases is the third leading cause of death among young children. Now a study offers a way to predict the risk of such deadly outbreaks using AI modeling, giving public health systems weeks or even months to prepare and to save lives.

A new study of a city in the Democratic Republic of Congo finds that the necessary process of decarbonization is repeating and recreating colonial inequalities.

The Sverris saga describes how castle invaders “took a dead man and cast him unto the well, and then filled it up with stones”, in what may have been an early act of biological warfare - and now researchers believe they have found the skeleton of the man in question