Latest news with #blackhole
Yahoo
4 days ago
- Science
- Yahoo
Rogue black hole found terrorizing unfortunate star in distant galaxy
When you buy through links on our articles, Future and its syndication partners may earn a commission. A rogue, middle-mass black hole has been spotted disrupting an orbiting star in the halo of a distant galaxy, and it's all thanks to the observing powers of the Hubble Space Telescope and Chandra X-ray Observatory. However, exactly what the black hole is doing to the star remains in question as there are conflicting X-ray measurements. Black holes come in different size classes. At the smaller end of the scale are the stellar-mass black holes born in the ashes of supernova explosions. At the top end of the scale are the supermassive black holes, which can grow to have many millions or billions of times the mass of our sun, lurking in the hearts of galaxies. In between those categories are intermediate-mass black holes (IMBH), which have mass ranging from hundreds up to 100,000 solar masses, or thereabouts. "They represent a crucial missing link in black hole evolution between stellar mass and supermassive black holes," Yi-Chi Chang of the National Tsing Hua University in Hsinchu, Taiwan said in a statement. The problem is that intermediate-mass black holes are hard to find, partly because they tend not to be as active as supermassive black holes or as obvious as a stellar-mass black hole when its progenitor star goes supernova. However, occasionally, an IMBH will spark to life when it instigates a tidal disruption event. This happens when a star or gas cloud gets too close to the black hole and gravitational tidal forces rip the star or gas cloud apart, producing bursts of X-rays. "X-ray sources with such extreme luminosity are rare outside galaxy nuclei and can serve as a key probe for identifying elusive IMBHs," said Chang. In 2009, Chandra spotted anomalous X-rays originating from a region 40,000 light-years from the center of a giant elliptical galaxy called NGC 6099, which lies 453 million light-years from us. This bright new X-ray source was called HLX-1, and its X-ray spectrum indicated that the source of the X-rays was 5.4 million degrees Fahrenheit (3 million degrees Celsius), a temperature consistent with the violence of a tidal disruption event. But what followed was unusual. The X-ray emissions reached a peak brightness in 2012 when observed by the European Space Agency's XMM-Newton X-ray space telescope. When XMM-Newton took another look in 2023, it found the X-ray luminosity had substantially dwindled. In the meantime, the Canada–France Hawaii Telescope had identified an optical counterpart for the X-ray emission, one that was subsequently confirmed by Hubble. There are two possible explanations for what happened. The first is that Hubble's spectrum of the object shows a tight, small cluster of stars swarming around the black hole. The black hole might have once been at the core of a dwarf galaxy that was whittled down — unwrapped like a Christmas present — by the gravitational tides of the larger NGC 6099. This process would have stolen away all the dwarf galaxy's stars to leave behind a free-floating black hole with just a small, tight grouping of stars left to keep it company. But the upshot of this is that the cluster of stars is like a stellar pantry to which the black hole occasionally goes to feast. It seems certain that a tidal disruption event involving one of these stars is what Chandra and Hubble have witnessed, but was the star completely destroyed? One possibility is that the star is on a highly elliptical orbit, and at its perihelion (closest point to the black hole) some of the star's mass is ripped away — but the star managed to survive for another day. This would potentially explain the X-ray light curve: The emission from 2009 was as the star was nearing perihelion, while the peak in 2012 was during perihelion, and the latest measurements in 2023 would be when the star was farthest from the black hole and not feeling its effects so much. We might then expect another outburst of X-rays during its next perihelion, whenever that might be. However, there's an alternative hypothesis: The star may have been stripped apart a piece at a time, forming a stream of material around the black hole. When Chandra first detected the X-ray emission from the tidal disruption event, this stream was just beginning to wrap back on itself, the self-intersection giving rise to shock-heating that produced X-rays. Then, the 2012 measurements would have been of a fully-fledged hot accretion disk of gas, the star by now completely ripped apart. The material within this disk would have spiraled into the black hole's maw, thus depleting the disk, which would explain why it is much less luminous in X-rays in 2023. Picking out the correct scenario apart will require further surveillance. "If the IMBH is eating a star, how long does it take to swallow the star's gas? In 2009, HLX-1 was fairly bright. Then, in 2012, it was about 100 times brighter, and then it went down again," Roberto Soria of the Italian National Institute for Astrophysics (INAF), who is a co-author of a new study describing the observations of HLX-1, said in the statement. "So now we need to wait and see if it's flaring multiple times, or if there was a beginning, a peak, and now it's just going to go down all the way until it disappears." Making new observations of an IMBH such as HLX-1 is key to better understanding the role they play in the black hole ecosystem. One model suggests that supermassive black holes might form and grow through the merger of many IMBH, but nobody knows how common intermediate-mass black holes are in the universe. "So if we are lucky, we're going to find more free-floating black holes suddenly becoming X-ray bright because of a tidal disruption event," said Soria. "If we can do a statistical study, this will tell us how many of these IMBHs there are, how often they disrupt a star, [and] how bigger galaxies have grown by assembling smaller galaxies." RELATED STORIES — Rogue black hole spotted on its own for the first time — Astronomers may have discovered the closest black holes to Earth — Hubble Telescope sees wandering black hole slurping up stellar spaghetti Alas, Chandra, XMM-Newton and Hubble all have small fields of view, meaning that they only see small patches of the sky. Because we don't know where the next tidal disruption event might take place, the chances of our space telescopes looking in the right place at the right time are slim. In essence, Chandra got lucky back in 2009. Fortunately, help is now on hand. The Vera C. Rubin Observatory comes fully online later this year to begin a 10-year all-sky survey, and spotting the flares of tidal disruption events will be a piece of cake for it. Once it finds such an event, Hubble and Chandra will know where to look and can follow up on it. IMBHs have remained mostly hidden for now, but their time in the shadows is coming to an end. The findings were published on April 11 in The Astrophysical Journal.
Yahoo
4 days ago
- Science
- Yahoo
Astronomers Peer Through Stellar Dust to See Black Holes Eating Whole Stars
In a new study, astronomers used the James Webb Space Telescope to study black hole events that would otherwise have been impossible to see—and in the process, they proved that dormant black holes aren't so dormant, after all. A dormant black hole isn't really inactive; it's just all alone. Without any meaningful amount of material around to pull in, a black hole will simply fly through space and present virtually no signal for astronomers looking to find it. Though its mass will bend light in the same characteristic ways as any other black hole, astronomers generally need to see its effect on surrounding matter to identify candidate regions of the sky worth studying at all. An artist's impression of a tidal disruption event. Credit: ESO/L. Calçada However, these 'dormant' singularities will occasionally come into contact with stars and other objects as they move around the galaxy. If they come too close, these objects are gobbled up by the black holes. When the object is a large star, it can be ripped physically apart by the gravitational forces. This star-destroying process is what's known as a tidal disruption event, and it's associated with a huge emission of radiation whenever matter is pulled over the event horizon. Usually, some proportion of the matter is converted to energy and blasted out in a form that astronomers can see. The problem is that very dusty galaxies can hide these events, blocking the X-ray or visible light emissions and hiding information that could help understand black holes and their galaxies. These researchers had previously supposed that in such cases, the radiation from the tidal disruption event should interact with the dust blocking it, producing infrared light that could be detected instead. The James Webb Space Telescope. Credit: NASA So they turned to the Webb telescope, the most advanced infrared detector in existence, to look for these characteristic signals—and found them. The issue was that these galaxies didn't appear to have the structure of an active black hole with a permanent accretion disc. Instead, they looked to be dormant black holes that were transiently eating up a star, producing a short burst of radiation, and then going back to quiescence. Tidal disruption events are surprisingly rare to see, with only a few dozen having been seen in total, but many scientists believe they are actually more common, and just often hidden from view. This study shows how even occluded black holes could be studied in the future—and that even hard-to-study singularities will often provide useful inroads for experimentation.
Yahoo
23-07-2025
- Science
- Yahoo
Yes, It's Possible to Safely Jump Into a Black Hole, Scientists Say
Here's what you'll learn when you read this story: Scientists say humans could indeed enter a black hole to study it. Of course, the human in question couldn't report their findings—or ever come back. The reason is that supermassive black holes are much more hospitable. In a finding ripped from Interstellar, scientists say humans can indeed explore black holes firsthand. The catch? If you're going to jump into a black hole, don't plan on ever jumping back out into our universe. 'A human can do this only if the respective black hole is supermassive and isolated, and if the person entering the black hole does not expect to report the findings to anyone in the entire Universe,' Grinnell College physicists explain in a new article in The Conversation. That's because of special physics found in supermassive black holes, resulting in a combination of gravity and event horizon that wouldn't instantaneously pull the human being into a very dead piece of spaghetti. Because supermassive black holes are much bigger than stellar and intermediate black holes, all the parts of them are more spread out. A person falling in would make it to the event horizon—the border of the black hole beyond which not even light can escape, and where gravity is so strong that light will orbit the black hole like planets orbit stars—a lot sooner than in a smaller black hole. The person would stay cognizant and intact for longer. But, of course, they would never emerge—making this a one-way rollercoaster ride of scientific discovery into oblivion. Why does the math work this way? It's a matter of facts about black holes of different sizes, the researchers say: 'For a black hole with a mass of our Sun (one solar mass), the event horizon will have a radius of just under 2 miles. The supermassive black hole at the center of our Milky Way galaxy, by contrast, has a mass of roughly 4 million solar masses, and it has an event horizon with a radius of 7.3 million miles or 17 solar radii. This implies, due to the closeness of the black hole's center, that the black hole's pull on a person will differ by a factor of 1,000 billion times between head and toe, depending on which is leading the free fall.' This means avoiding 'spaghettification' (really!) and a safe, gentle float past the event horizon. Why does stuff go in but never come out? Well, scientists have only begun to understand the specific instances in which black holes eject energy or information—and that's unlikely to ever take the form of a missive, or even Morse code message, from a disappearing astronaut. Those black holes are very old, for example, with different physics than this special case. But, like in Interstellar, our imaginations reel at the idea of studying a black hole from the inside. Perhaps in some far future, someone will invent the right kind of tether to pull someone back out. And in that case, we can confirm some of the facts of life in a black hole, time dilation or not. Get the Issue Get the Issue Get the Issue Get the Issue Get the Issue Get the Issue Get the IssueGet the Issue Get the Issue You Might Also Like The Do's and Don'ts of Using Painter's Tape The Best Portable BBQ Grills for Cooking Anywhere Can a Smart Watch Prolong Your Life? Solve the daily Crossword
Yahoo
21-07-2025
- Science
- Yahoo
Scientists Found a Black Hole That Shouldn't Exist. Now Physics Has a Problem.
Here's what you'll learn when you read this story: Over the past decade, the LIGO-Virgo-KAGRA (LVK) network has detected hundreds of black hole mergers, but none quiet as large as GW231123. At 225 solar masses, the black hole resulting from the merger far exceeds previous record holder GW190521, which weighed in at 140 solar masses. This black holes involved in this merger were actually so large that they challenge some of our understanding of stellar evolution. The Laser Interferometer Gravitational-wave Observatory, or LIGO, made major headlines in 2015 when scientists confirmed the first ever detection of gravitational waves—ripples in spacetime caused by highly energetic deep space phenomena (think: black hole mergers, supernovae, and neutron star collisions). This particular detection originated from a black hole merger that created a new black hole 62 times the mass of our Sun. The LIGO-Virgo-KAGRA (LVK) network of gravitational wave detectors hasn't let off the gas in the decade since, and has made hundreds of confirmed gravitational-wave detections, including the first neutron star merger in 2017 and the largest black hole merger (clocking in at 140 solar masses) in 2021. Now, in a preprint uploaded to the arXiv server, LVK scientists have provided evidence that there's a new heavyweight champion—a merger that produced a new 255-solar-mass black hole. Designated GW231123 for the date it was discovered (November 23, 2023, during the fourth observing run of the LVK network), this black hole is actually too big, according to our current best understanding of physics. 'This is the most massive black hole binary we've observed through gravitational waves, and it presents a real challenge to our understanding of black hole formation,' Mark Hannam, a member of the LVK Collaboration from Cardiff University, said in a press statement. 'Black holes this massive are forbidden through standard stellar evolution models.' To form this black hole, the two black hole predecessors likely had to measure around 100 and 140 times the mass of the Sun, respectively. This means they potentially lie in what's known as the 'upper-mass gap'—a range of masses in which black holes aren't thought to form from stars directly (the resulting supernovae of these hugely massive stars should leave behind no stellar remnant at all). 'One possibility is that the two black holes in this binary formed through earlier mergers of smaller black holes." Hannam said. However, these black holes' masses aren't the only mystery, as both were spinning between 80 and 90 percent of their top speed limit. This makes them the highest spinning black holes ever recorded by LVK. 'The black holes appear to be spinning very rapidly—near the limit allowed by Einstein's theory of general relativity,' Charlie Hoy, another member of the LVK from the University of Portsmouth, said in a press statement. 'That makes the signal difficult to model and interpret. It's an excellent case study for pushing forward the development of our theoretical tools.' Because the detectors are sensitive to black holes of around 100 solar masses, detecting one more than double that size certainly pushes LIGO to its limits. According to Science News, the LVK network was only able to detect the smallest blip from this merger, with only around 0.1 seconds detected at the tail end of the collision. LIGO's decades-long mission to detect gravitational waves has given scientists a whole new understanding of the universe, and nearly a decade after its first detection, it shows no signs of stopping. You Might Also Like The Do's and Don'ts of Using Painter's Tape The Best Portable BBQ Grills for Cooking Anywhere Can a Smart Watch Prolong Your Life? Solve the daily Crossword
CTV News
19-07-2025
- Science
- CTV News
‘Where do we come from?': U of M researchers help detect record-breaking black hole collision
CTV's Harrison Shin has more on the black hole discovery made by two University of Manitoba researchers. Two University of Manitoba researchers are exploring the cosmos with one philosophical question in mind. Dr. Samar Safi-Harb and postdoctoral fellow Nathan Steinle are part of a team using the Laser Interferometer Gravitational-Wave Observatory (LIGO), a facility capable of detecting gravitational waves. 'Not everything in the universe can be seen with light, and gravitational waves are a new way of looking at the universe. These are ripples in the fabric of space-time,' Safi-Harb said. LIGO recently detected a collision between two black holes — an event that stands out for its scale. 'It's the most massive black hole merger detected by LIGO. And by 'most massive,' I mean each of these black holes is more than 100 times the mass of the sun,' she said. Until now, black holes of this size had not been directly observed. LIGO's detection provides the first direct evidence of their existence, according to Safi-Harb. Steinle said the discovery raises fundamental questions. 'It's so important because we're not sure if there's an upper limit on the mass. Can it keep getting bigger and bigger until we all grow old?' he said. He added that the finding is just the beginning. 'It really gives you great hope. Once future detectors are built — and they'll have at least 10 times better sensitivity — we'll be able to do a lot more,' he said. For Safi-Harb, the discovery brings scientists one step closer to understanding the universe. 'Finding these extreme events — whether through light, gravitational waves or other cosmic messengers — really brings us a bit closer to understanding our cosmic origins,' she said.
