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One in five adults worldwide is living with fatigue. The general advice is to “do more” - but this isn’t the only solution to our exhaustion epidemic, says Amy Arthur

Millions of people experience symptoms many doctors dismiss as imaginary, but why? Caroline Crampton's moving first-person account is very revealing

Negative thinking is unpopular but it could drive more realistic efforts to limit harm from global warming

Caused by debris from a comet thought to originate in the Oort Cloud, the Lyrid meteor shower peaks this year on 22 April and is best viewed from the northern hemisphere, says Abigail Beall

Astronomers have found the largest stellar mass black hole in the Milky Way so far. At 33 solar masses, it dwarfs the previous record-holder, Cygnus X-1, which has only 21 solar masses. Most stellar mass black holes have about 10 solar masses, making the new one—Gaia BH3—a true giant.

Supermassive black holes (SMBH) like Sagittarius A Star at the heart of the Milky Way capture most of our black hole attention. Those behemoths can have billions of solar masses and have enormous influence on their host galaxies.

But stellar-mass holes are different. Unlike SMBHs that grow massive through mergers with other black holes, stellar black holes result from massive stars exploding as supernovae. SMBHs are always found in the center of a massive galaxy, but stellar black holes can be hidden anywhere.

“This is the kind of discovery you make once in your research life.”

Pasquale Panuzzo, National Centre for Scientific Research (CNRS) at the Observatoire de Paris

Astronomers found BH3 in data from the ESA’s Gaia spacecraft. It’s Gaia’s third stellar black hole. BH3 has a stellar companion, and the black hole’s 33 combined solar masses tugged on its aged, metal-poor companion. The star’s tell-tale wobbling betrayed BH3’s presence. At only 2,000 light-years away, BH3 is awfully close in cosmic terms.

Astronomers have found the most massive stellar black hole in our galaxy, thanks to the wobbling motion it induces on a companion star. This artist’s impression shows the star’s orbits and the black hole, dubbed Gaia BH3, around their common centre of mass. The European Space Agency’s Gaia mission measured this wobbling over several years. Image Credit: ESO/L. Calçada

A new research letter in Astronomy and Astrophysics presented the discovery. Its title is “Discovery of a dormant 33 solar-mass black hole in pre-release Gaia astrometry.” The lead author is Pasquale Panuzzo, an astronomer from the National Centre for Scientific Research (CNRS) at the Observatoire de Paris.

“No one was expecting to find a high-mass black hole lurking nearby, undetected so far,” said Panuzzo. “This is the kind of discovery you make once in your research life.”

This black hole is remarkable for its considerable mass. Researchers have found stellar black holes with similar masses, but always in other galaxies. The size is confounding, but astrophysicists have pieced together how they may become so massive.

They could result from the collapse of metal-poor stars. These stars are composed almost entirely of hydrogen and helium, the primordial elements. Scientists think these stars lose less mass over their lifetimes of fusion than other stars. They retain more mass, so they collapse into more massive black holes. This idea is based on theory; there’s no direct evidence.

But BH3 could change that.

Binary stars tend to form together and have the same metallicity. Follow-up observations showed that BH3’s companion star is likely a remnant of a globular cluster that the Milky Way absorbed more than eight billion years ago. Since binary stars tend to have the same metallicity, this metal-poor companion bolsters the idea that low-metallicity stars can retain more mass and form larger stellar black holes. This is the first evidence supporting the idea that ancient and metal-poor massive stars collapse into massive black holes. It also supports the idea that these early stars may have evolved differently than modern stars of similar masses.

But there’s another interpretation.

Artist’s impression of a Type II supernova explosion, which involves the destruction of a massive supergiant star. When stars explode as supernovae, they eject matter into space, potentially polluting nearby companion stars. Image Credit: ESO

When stars explode as supernovae, they forge heavier elements that are blown out into space. Shouldn’t the companion show evidence of contamination by the metals from BH3’s supernova?

“What strikes me is that the chemical composition of the companion is similar to what we find in old metal-poor stars in the galaxy,” explains Elisabetta Caffau of CNRS, Observatoire de Paris, also a member of the Gaia collaboration. “There is no evidence that this star was contaminated by the material flung out by the supernova explosion of the massive star that became BH3.” From this perspective, the pair may not have formed together. Instead, the black hole could’ve acquired its companion only after its birth, capturing it from another system.

BH3 and the two other black holes found by Gaia are dormant. That means there’s nothing close enough for them to “feed” on. Even though BH3 has a companion, it’s about 16 AU away. If BH3 was actively accreting matter, it would release energy that would betray its presence. Its dormancy enabled it to remain undetected.

Simulation of glowing gas around a spinning black hole. As the gas heats up, it emits energy that makes it visible. If the black hole has no nearby companion, it’s dormant and harder to find. Image Credit: Chris White, Princeton University

At only 2,000 light years away, astronomers are bound to keep studying BH3.

“Finally, the bright magnitude of the system and its relatively small distance makes it an easy target for further observations and detailed analyses by the astronomical community,” the discoverers write in their research letter.

This discovery may have been serendipitous, but it was no accident. A dedicated team of researchers scours Gaia data for stars with odd companions. This includes light and heavy exoplanets, other stars, and black holes. Gaia can’t spot planets or dormant black holes but can spot their effect on their stellar companions.

The researchers behind the discovery released their findings before Gaia’s next official data release. They felt it was too important to sit on. “We took the exceptional step of publishing this paper based on preliminary data ahead of the forthcoming Gaia release because of the unique nature of the discovery,” said co-author Elisabetta Caffau, also a Gaia collaboration member and CNRS scientist from the Observatoire de Paris – PSL.

“We have been working extremely hard to improve the way we process specific datasets compared to the previous data release (DR3), so we expect to uncover many more black holes in DR4,” said Berry Holl of the University of Geneva, in Switzerland, member of the Gaia collaboration.

“This discovery should also be seen as a preliminary teaser for the content of Gaia DR4, which will undoubtedly reveal other binary systems hosting a BH,” the authors conclude.

Gaia DR4 is scheduled to be released no sooner than the end of 2023. If past data releases are any indication, the data will be full of new discoveries. If there are enough binary stellar mass black holes in the data, astronomers may get closer to understanding where they come from and if massive stars behaved differently in the early Universe.

The post The Milky Way’s Most Massive Stellar Black Hole is Only 2,000 Light Years Away appeared first on Universe Today.

Astronomers have discovered methane emission on a brown dwarf, an unexpected finding for such a cold and isolated world. The findings suggest that this brown dwarf might generate aurorae similar to those seen on our own planet as well as on Jupiter and Saturn.

Scientists have developed a new method using knot theory to find the optimal routes for future space missions without the need to waste fuel.

In some materials, spins form complex magnetic structures within the nanometer and micrometer scale in which the magnetization direction twists and curls along specific directions. Examples of such structures are magnetic bubbles, skyrmions, and magnetic vortices. Spintronics aims to make use of such tiny magnetic structures to store data or perform logic operations with very low power consumption, compared to today's dominant microelectronic components. However, the generation and stabilization of most of these magnetic textures is restricted to a few materials and achievable under very specific conditions (temperature, magnetic field...). Physicists have now investigated a new approach that can be used to create and stabilize complex spin textures, such as radial vortices, in a variety of compounds.

A team has constructed an improved mid-infrared microscope, enabling them to see the structures inside living bacteria at the nanometer scale. Mid-infrared microscopy is typically limited by its low resolution, especially when compared to other microscopy techniques. This latest development produced images at 120 nanometers, which the researchers say is a thirtyfold improvement on the resolution of typical mid-infrared microscopes. Being able to view samples more clearly at this smaller scale can aid multiple fields of research, including into infectious diseases, and opens the way for developing even more accurate mid-infrared-based imaging in the future.

Researchers have used artificial intelligence techniques to massively accelerate the search for Parkinson's disease treatments. The researchers designed and used an AI-based strategy to identify compounds that block the clumping, or aggregation, of alpha-synuclein, the protein that characterises Parkinson's.

While the electronic tongue bears little physical resemblance to its namesake, the strand-like sensory probes of the 'e-tongue' still outperformed human senses when detecting contaminated wine in a recent study. In a recent experiment, the e-tongue identified signs of microorganisms in white wine within a week after contamination -- four weeks before a human panel noticed the change in aroma. This was also before those microbes could be grown from the wine in a petri-dish. Winemakers traditionally rely on these two methods, sniffing the wine and petri-dish testing, to identify potential wine 'faults' or spoilage.

More than five million central lines are placed in patients who need prolonged drug delivery, such as those undergoing cancer treatments, in the United States every year, yet the common procedure can lead to a bevy of complications in almost a million of those cases. Researchers developed a robotic simulation training program to provide trainee physicians with more practice on the procedure. A year after deploying the program the team found that all complication types -- mechanical issues, infections and blood clots -- were significantly lower.

More than five million central lines are placed in patients who need prolonged drug delivery, such as those undergoing cancer treatments, in the United States every year, yet the common procedure can lead to a bevy of complications in almost a million of those cases. Researchers developed a robotic simulation training program to provide trainee physicians with more practice on the procedure. A year after deploying the program the team found that all complication types -- mechanical issues, infections and blood clots -- were significantly lower.

Engineers have developed a record-setting nanomaterial which when stretched in one direction, expands perpendicular to the applied force.

We know there is some connection between skin and gut health, but many assumed the gut was the one calling the shots. A new study suggests that the influence can go the other way

A quick reminder, to those in the northwest’s big cities, that I will be giving two talks about my book in the next 48 hours:

• At Seattle’s Town Hall, tonight (April 17th) at 7:30 pm.
• Near Portland, at the Cedar Hills branch of Powell’s Books, tomorrow (April 18th) at 7:00 pm.

Hope to see some of you there! (You can keep track of my speaking events at my events page.)

A computer intended to mimic the way the brain processes and stores data could potentially improve the efficiency and capabilities of artificial intelligence models

Weeding robots can sometimes struggle to tell weeds from crops, but genetically modifying the plants we want to keep to make them brightly coloured would make the job easier, suggest a group of researchers

Investigations of the paradoxical link between tinnitus and hearing loss have revealed a hidden form of deafness, paving the way to possible new treatments

I forgot that Columbia University officials are being grilled in Congress about anti-semitism on its campus. You can watch it live below, and things are getting heated, as they did in the House hearings involving the presidents of MIT, Harvard, and Penn. The Republicans are loaded for bear, but I think I’ll have to watch most of this later. CNN has an article, with a live feed, about what’s going on. Here is some of their news:

All four Columbia officials testifying before Congress unequivocally stated that calls for the genocide of Jews violate the university’s code of conduct.

Rep. Suzanne Bonamici asked Columbia President Minouche Shafik, board co-chairs David Greenwald and Claire Shipman and David Schizer, co-chair of a task force on antisemitism, for a simple yes or no response. All four said “yes,” calls for the genocide of Jews would violate Columbia’s code of conduct.

The response offered a stark contrast to the lawyerly answers that university presidents provided during the December hearing before the same committee. That moment went viral, sparking an uproar that eventually contributed to the ousters of the presidents of Harvard and the University of Pennsylvania.

Of course, the Columbia officials had the advantage of having months to prepare for that question.

Days after the December hearing, Columbia issued a statement saying: “Calls for genocide against the Jewish community or any other group are abhorrent, inconsistent with our values and against our rules.”

Columbia certainly has learned from what happened in the last hearings! But apparently Columbia doesn’t adhere to the First Amendment, under which calls for genocide are, under many circumstances, legal. This means that their code of conduct does not completely comport with the First Amendment.

Here, quickly, are the YouTube notes:

The Committee on Education and the Workforce, chaired by Virginia Foxx (R-NC), will hold a hearing to call on the leadership at Columbia University to answer for the rampant antisemitism engulfing their campuses and threatening their Jewish students.

 

Here’s FIRE’s free-speech ranking for Columbia University. It’s below average: #214 out of #248 schools (Harvard was the lowest). Click to look it up: