Latest news with #LIGO
Hindustan Times
a day ago
- Science
- Hindustan Times
Violent Collision of Two Black Holes Rippled Across the Universe
Astrophysicists have discovered the largest known merger of two black holes to form a larger single hole about 225 times the mass of the sun. The violent collision between the spinning objects, one about 100 times the mass of the sun and the other about 140 times that amount, produced a gravitational wave that rippled across the universe. Scientists detected the faint signal using the Laser Interferometer Gravitational-Wave Observatory (LIGO), a facility that uses 2.5-mile long, L-shaped instruments in Hanford, Wash., and Livingston, La., in unison to detect and measure cosmic gravitational waves. The signal, only 0.2 second long, was picked up in 2023 and announced July 13 at a conference in Glasgow. The findings have been posted ahead of peer review on the preprint server arXiv. A black hole is an astronomical object with a gravitational pull so strong that nothing, not even light, can escape. While scientists have predicted the existence of black holes since the 18th century, direct evidence has only turned up recently. In 2015, scientists used the LIGO to make the first-ever detection of a gravitational wave, a distortion in the fabric of space caused by the acceleration of massive objects such as black holes or neutron stars. Gravitational waves carry information about their origins and the nature of gravity itself. The effort won the researchers a Nobel Prize in 2017. In 2019, scientists released the first image of a black hole at the center of a galaxy roughly 55 million light years from Earth, showing a fuzzy ring of oranges and yellows surrounding a dark center, where light is trapped by the object's massive gravitational pull. Because the 2023 gravitational wave only produced a small amount of data, scientists don't know exactly how far away the object is. 'It's kind of ridiculous to say, but it's sort of between three or four billion light years away and 12 to 13 billion light years away,' said Mark Hannam, an astrophysicist at the University of Cardiff in the U.K., and a member of the scientific team that discovered the object, named GW231123 for 'gravitational wave' and the date it was discovered. Hannam said there is still a lot that scientists are learning and that the two black holes could have formed through earlier mergers of even smaller black holes. 'We don't know how many black holes were merged in this process,' Hannam said. The two black holes could also have formed from stars colliding and forming more massive, highly spinning stars which then collapsed to form black holes, according to Vicky Kalogera, professor of physics and astronomy at Northwestern University and a member of the team that analyzed the signal. Either way, this finding has opened up new lines of research using gravitational wave detectors, according to Alessandra Corsi, professor of physics and astronomy at Johns Hopkins University who wasn't involved in the paper. 'What excites me is finding different ways of studying the cosmos that are telling you, hey, there's surprising things that are going on,' she said. Write to Eric Niiler at
Yahoo
2 days ago
- 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
5 days ago
- 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.
The Hindu
5 days ago
- Science
- The Hindu
New gravitational waves reveal black hole with ‘forbidden' mass
Scientists working with a network of observatories located around the world recently reported that they had detected a powerful and unusual burst of gravitational waves, which they called GW231123. The signal was traced back to two black holes colliding into each other on November 23, 2023. This isn't the first time the observatories have detected gravitational waves, but the event is special because of the extraordinary size of the black holes involved: they are much heavier than most seen before. More interesting is the fact that the heavier black hole appeared to have a 'forbidden' mass — a value inside a range called the pair instability mass gap — which challenges what physicists thought was possible for black holes created from dying stars. Imagine a massive star at the end of its life. Usually, very heavy stars explode in supernovae, leaving behind black holes. But theory predicts that no black holes should form with masses between about 60 and 130 times the mass of our sun. This is the pair instability mass gap: it's thought to exist because stars this large explode so violently that nothing remains, not even a black hole, just scattered gas. Above 130 solar masses, stars may skip the explosion and directly collapse to create supermassive black holes. So finding black holes in the mass gap raises important questions about how they got there. On November 23, 2023, the two Laser Interferometer Gravitational-wave Observatories (LIGO) in the U.S. detected a burst of gravitational waves, faint ripples in spacetime created by massive objects accelerating and colliding. The GW231123 event lasted only about one-tenth of a second and the signal was strong and clear. The collision happened about 2 billion lightyears away. Scientists at the LIGO as well as Virgo and KAGRA observatories in Italy and Japan, respectively, conducted a detailed analysis and determined the pre-merger mass of the two colliding black holes. The heavier one had 120-159 solar masses but likely centred at 137 solar masses. The lighter one weighed 51-123 solar masses but likely centred at 103 solar masses. The total mass involved in the collision was thus likely 190-265 solar masses, rendering GW231123 the most massive black hole merger ever seen with high confidence. The mass of the heavier black hole in the merger is right inside, or just above, the pair instability mass gap. The mass of the lighter one could also be in or near the gap, given the large uncertainty. According to theory, stars can't leave behind black holes in this range, so the scientists figure something else must be going on. They are already considering several explanations. One, for example, is called a hierarchical merger: smaller black holes could merge inside dense star clusters, then the resulting larger black holes merge again, building up over time and ending up inside the gap. This possibility finds some support from the fact that both black holes were spinning rapidly. Usually, black holes formed from individual stars aren't spinning this fast. Another possibility is a stellar merger. Sometimes, two stars might merge before they die, creating a much larger star that might collapse to form a black hole whose mass lands inside the gap. It's also possible these two black holes formed right after the Big Bang, by a process unrelated to stars, although this idea is in the realm of speculation. Yet other potential explanations include some stars losing less mass before exploding or hitherto entirely unknown processes. The main idea is that the detection of GW231123 suggests the universe can make black holes in the mass gap after all, and not just through the collapse of single stars. And that this fact means scientists' theories about the lives and deaths of massive stars need updating.
Yahoo
6 days ago
- Science
- Yahoo
Scientists record a black hole collision they weren't sure was possible
A pair of newly-discovered record-breaking black holes has scientists simultaneously popping the champagne and scratching their heads. The massive duo are the largest ever recorded at the Laser Interferometer Gravitational-Wave Observatory (LIGO), which was built to detect ripples in the fabric of spacetime caused by the collisions of massive objects. These enormous outliers are challenging theorists to figure out just how they grew to such titanic sizes. 'We don't think black holes form between about 60 and 130 times the mass of the sun, and these two seem to be pretty much slap bang in the middle of that range,' says Mark Hannam, a physicist at Cardiff University in the UK and a LIGO team member. Your normal everyday black hole is thought to be born during the death of a giant star, when the star's weighty core collapses down into an infinitesimal point with such strong gravity that nothing, not even light, can escape it. But the physics of this process gets wonky for especially huge stars. Once their cores weight more than around 60 solar masses, the collapse becomes so violent that the entire star is blown to smithereens, leaving nothing, not even a black hole, behind. Yet LIGO is now spotting more and more black holes within this 'forbidden' zone, including the newest behemoths. They are thought to be 103 and 137 times the sun's mass, according to a paper posted July 13 to but each has enough uncertainty in their measured properties that they could both be inside the prohibited range. When they met and merged out in the deep dark universe billions of years ago, they created an even larger monster tipping the scales at between 190 and 265 solar masses, the most massive beast LIGO has ever seen. As the observatory captures gravitational waves from more such events, researchers will be able to tease apart the mystery of their creation and perhaps learn whether they have a connection to the astoundingly huge black holes lurking in the centers of galaxies. Black holes were thought to come in two flavors. This discovery is a strange third For a long time, black holes were known to come in just two versions—approximately sun-sized and galactic. Most of the roughly 300 black holes LIGO has detected so far fit into the first category: They are between a few and several tens of times the sun's mass and are believed to have formed after a gargantuan star exploded as a supernova, leaving behind a dense remnant that inexorably sucks in anything that gets too close. The second version is a much more gargantuan beast. Telescopes have spotted black holes in the centers of nearly every galaxy; gravitational monstrosities weighing 100 million solar masses or more that appear to regulate star formation within these galaxies. Nobody is quite sure how these immense devourers got so big. Did they start out as sun-scale black holes and then somehow grow to extreme size? Or was there another story behind their creation? The existence of black holes in the intermediate range—somewhere between 100 and 100,000 times the sun's mass—would help bridge this gap and perhaps help explain whether small black holes were turning into larger ones. But, until recently, physicists had never seen one. To great fanfare in 2020, LIGO researchers announced that they'd found a black hole duo with masses 66 and 85 times that of the sun, whose smash-up produced a giant with around 150 solar masses. The finding for the first time showed that black holes could cross into this threshold of intermediate mass, though theorists are still debating exactly how that happened. The problem is that when a gigantic star has a core that weights between 60 and 130 times the sun's mass, it can reach blazing temperatures nearing 300 million degrees Celsius during the end of its life. At that point, particles of light spontaneously transform into electrons and their antimatter counterparts, positrons. These particles can no longer hold up the star's heavy outer layers, which come crashing down with such ferocity that the core is completely obliterated. No black hole, or anything else, results. Physicists have speculated about a few possibilities to explain what they're seeing with LIGO. For one, their theories of stellar evolution might be wrong and perhaps something can survive the severe core collapse of humongous stars. The other possibilities involve smaller black holes growing into larger ones via some kind of two-step process, says astrophysicist Priyamvada Natarajan of Yale University in Connecticut. It could be either that two star-sized black holes came together and combined to form heavier behemoths or a small black hole was created and then sucked down gas and dust to balloon into a more massive beast. 'The question is: What are the cosmic environments and conditions where such things can happen?' Natarajan asks. One major clue might lie with the two new objects, which are spinning around like a top at close to the upper limit that scientists think they can spin. They have the fastest rotations of any black hole LIGO has ever seen. Some researchers have posited such spins could arise when smaller black holes meet, merge, and spin each other up. But Natarajan thinks perhaps something else is going on here. Because if the colliding black holes were spinning in opposite directions (and there's a good chance they were) the merger black hole would have produced a slower-spinning object. She favors the idea that smaller black holes were born in dense stellar clusters full of gas and dust. As that star-sized black hole bounced around inhaling material like water going down a drain, it could have grown and spun up to the extreme rotation seen in the new objects. She and her colleagues are working to calculate the exact outcome of such a feasting process in stellar clusters. Scientists aren't done searching for enormous black holes Future upgrades to the LIGO detectors will make them more sensitive, letting them uncover even more enormous black holes and measure their properties more precisely. Along with gravitational wave detectors in Europe, Japan, and eventually India, researchers will be able to pinpoint black hole events better on the night sky, allowing telescopes to scope those areas out and see if there's, for instance, a dense star cluster that might favor one formation mechanism or another. Researchers are also looking forward to instruments such as the Cosmic Explorer and Einstein Telescope, expected to be operational in the mid-2030s or 40s, which will be able to see black hole mergers that occurred much earlier in the universe's history. Such gravitational wave observatories might be able to capture events when galaxies were first forming, potentially providing insights into how their central black holes became so gargantuan, along with better data on small and intermediate black holes. 'There's just so many black holes littered in the universe,' says Natarajan. 'The fact that we're starting to bridge these scales, I think that's super exciting.' 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