Latest news with #cosmicExplosions
Yahoo
16 hours ago
- Science
- Yahoo
Astronomers Astonished by Largest Explosion Since the Big Bang
You've heard of how mighty supernovas are, or of the ungodly amounts of energy released by gamma ray bursts. But astronomers have just discovered a type of cosmic blast that puts all those to shame. They're called "extreme nuclear transients" (ENTs) — and they're quite literally the most powerful explosion witnessed since the dawn of time. What produces ENTs is appropriately catastrophic: a star, at least three times as massive as our Sun, being obliterated by a supermassive black hole. "We've observed stars getting ripped apart as tidal disruption events for over a decade, but these ENTs are different beasts, reaching brightnesses nearly ten times greater than what we typically see," Jason Hinkle, lead author of a new study published in the journal Science Advances, and a researcher at the University of Hawai'i's Institute for Astronomy (IfA), said in a statement about the work. "Not only are ENTs far brighter than normal tidal disruption events, but they remain luminous for years, far surpassing the energy output of even the brightest known supernova explosions," Hinkle added. The first clues emerged when Hinkle and his team were trawling through public data collected by the European Space Agency's Gaia mission, a vast three-dimensional map of over two billion stars and counting. Amid this stellar sea, they noticed flares of light, including one recorded in 2016 and another in 2018, that inexplicably lasted for several years. Most cosmic explosions, for comparison, only shine for several weeks. "When I saw these smooth, long-lived flares from the centers of distant galaxies, I knew we were looking at something unusual," Hinkle said. He wasn't the only one on the scent. Back in 2023, another team of astronomers reported a similar detection with the Zwicky Transient Facility in California. Following-up on these findings, Hinkle conducted additional observations with other telescopes, including the Keck Observatory in Hawaii, and linked these phenomena together. The most formidable ENT, assigned the screenname-esque moniker of Gaia18cdj, unleashed 25 times more energy than the most powerful supernova ever detected. In one year, it radiated energy equal to all the energy our Sun will produce in its entire lifetime across billions of years — times one hundred. Typically, a supernova produces "just" one Sun's worth of energy. To produce such a tremendous blast, a star has to undergo a brutal, slow death. That's what sets these apart from when a star falls into a black hole in a typical tidal disruption event, which culminates in a powerful but brief flash. An ENT draws out the torture, forming a disk of the star's shredded entrails that glows for years. This aspect of a supermassive black hole's diet could tell us a lot about how they grew to their monstrous masses — a mystery that has long haunted astronomers — and how they stamped their name on a crucial period of the universe's history. "By observing these prolonged flares, we gain insights into black hole growth when the universe was half its current age and galaxies were busy places — forming stars and feeding their supermassive black holes ten times more vigorously than they do today," said coauthor Benjamin Shappee, an associate professor at IfA, in a statement. "These ENTs don't just mark the dramatic end of a massive star's life. They illuminate the processes responsible for growing the largest black holes in the universe," Hinkle added. More on astronomy: Scientists Spot Mysterious Object in Our Galaxy Pulsing Every 44 Minutes
The Independent
3 days ago
- Science
- The Independent
Scientists find the most intense explosion ever seen in the universe
Scientists have discovered the most powerful blasts of energy in the known universe. Dubbed extreme nuclear transients, or ENTs, the cosmic explosions are unprecedented in their intensity. They happen when massive stars – much bigger than our Sun – go too close to a supermassive black hole and are torn to pieces. The resulting collision throws out vast amounts of energy that travel right across the cosmos. "We've observed stars getting ripped apart as tidal disruption events for over a decade, but these ENTs are different beasts, reaching brightnesses nearly ten times more than what we typically see," said Jason Hinkle, who led the study. 'Not only are ENTs far brighter than normal tidal disruption events, but they remain luminous for years, far surpassing the energy output of even the brightest known supernova explosions.' The most energetic ENT, for instance, throws out 25 times more energy than the most powerful known supernova. A supernova can emit as much energy a year as the Sun does over its 10-billion-year lifetime, but ENTs can emit 100 times that over a single year. The discovery came from work looking for flares that were being emitted from the centre of galaxies. In data from the European Space Agency 's Gaia telescope, Jason Hinkle spotted two strange flares that appeared to last longer than normal transients, and had other unexpected characteristics. "Gaia doesn't tell you what a transient is, just that something changed in brightness," said Hinkle. "But when I saw these smooth, long-lived flares from the centers of distant galaxies, I knew we were looking at something unusual." That began a years-long project to find out what the flares were coming from. Eventually, a third was found and further research showed that the ENTs were a new kind of unseen astrophysical event. The ENTs are notable not only for their intensity and unprecedented nature. Researchers also hope they can be used to better understand black holes – and the universe that holds them. "ENTs provide a valuable new tool for studying massive black holes in distant galaxies. Because they're so bright, we can see them across vast cosmic distances – and in astronomy, looking far away means looking back in time,' said Benjamin Shappee, a co-author on the study. 'By observing these prolonged flares, we gain insights into black hole growth when the universe was half its current age when galaxies were happening places—forming stars and feeding their supermassive black holes 10 times more vigorously than they do today." But such ENTs are hard to find, happening at least 10 million times left often than supernovae. Researchers hope that upcoming new equipment such as the Vera C Rubin Observatory and Nasa's Roman Space Telescope will allow for more of them to be discovered.
