Astronomers in Hawaii have discovered a new kind of explosion, and they’re the most energetic stellar explosions ever recorded.
An international team of researchers describes the discovery of this newly observed phenomenon in a study published Wednesday in the journal Science Advances, shedding light on events that will help astronomers study the distant universe.
Tidal disruptions consist of supermassive black holes tearing apart any star that wanders too close, so ENTs are a kind of tidal disruption.
Gaia18cdj, the team’s strongest documented ENT, released 25 times more energy than the most energetic supernovae known to science.
Nevertheless, their massive energy outputs will prove to be extremely useful for astronomers studying far-away massive black holes.
They are the most powerful stellar explosions ever observed, and astronomers in Hawaii have found a new type of explosion.
Presenting “extreme nuclear transients” (ENTs), which occur when stars at least three times as heavy as the Sun are destroyed by supermassive black holes, causing a massive energy release. In a study released Wednesday in the journal Science Advances, an international team of researchers details the discovery of this recently noticed phenomenon, providing insight into events that will aid astronomers in their study of the far-off cosmos.
“For more than ten years, we have seen stars being torn apart by tidal disruption events, but these ENTs are different beasts, reaching brightnesses nearly ten times more than what we typically see,” said Jason Hinkle, the study’s lead author and PhD candidate at the University of Hawaii’s Institute for Astronomy, in a W. Statement from the M. Keck Observatory. ENTs are a form of tidal disruption, which occurs when supermassive black holes tear apart any star that approaches too closely.
He continued, “ENTs are not only much brighter than typical tidal disruption events, but they also last for years and produce far more energy than even the brightest known supernova explosions.”.
It was almost by chance that they were discovered. Hinkle discovered two odd signals from 2016 and 2018 while looking through data from the European Space Agency’s Gaia mission for persistent flares extending from galaxies’ centers. This discovery sparked a multi-year investigation. Meanwhile, two different groups discovered a similar 2020 flare in the Zwicky Transient Facility (ZTF), an astronomical survey. Other information from the W. The 2020 event was verified to be similar to the two Gaia events by the M. Keck Observatory in Hawaii.
Hinkle and his associates came to the conclusion that these stellar explosions weren’t your typical ones because they released more energy than any supernova that science is aware of. A supermassive black hole actively absorbing material—a process known as accretion—was indicated by the event’s light curves and the massive energy release. These astrophysical events, however, clearly involve a supermassive black hole systematically shredding and eating a giant star, in contrast to regular black hole accretion, which causes nearby matter to heat up and project irregular light, the astronomers found.
ENTs are the universe’s most energetic known explosions. The team’s most powerful recorded ENT, Gaia18cdj, emitted 25 times as much energy as the most powerful supernovae currently understood. In general, each ENT emits the same amount of energy as 100 Suns would during their 10-billion-year lifetimes. In contrast, a typical supernova typically releases energy equivalent to that of a single Sun.
Hinkle explained, “These ENTs don’t just signify the dramatic end of a massive star’s life.”. They provide insight into the mechanisms underlying the universe’s biggest black hole formation. Additionally, ENTs are at least 10 million times less common than supernovae. However, astronomers studying distant massive black holes will find great value in their enormous energy outputs.
“We can see them over great cosmic distances because they are so bright—and in astronomy, looking far away means looking back in time,” said Benjamin Shappee, an associate professor at the University of Hawaii’s Institute for Astronomy and a co-author of the study. We can learn more about the growth of black holes by studying these extended flares. This is because the universe was half as old at cosmic noon, when galaxies were forming stars and feeding their supermassive black holes ten times more vigorously than they do now. “”.
