Astronomers have detected the largest cosmic explosion ever recorded – and it lasted more than three years.
The explosion, dubbed AT2021lwx, is thought to be the result of a cloud of solid gas — thousands of times larger than the sun — being sent into the black hole after being de-orbited.
Fragments of the cloud would be engulfed, forming a large dusty “doughnut” around the black hole.
Astronomers say such events are rare, but nothing of this magnitude has been seen before.
University of Southampton researcher Dr Philip Wiseman, who led the study, said: “We found this by accident because when we searched for a type of supernova it was flagged by our search algorithm.
“Most supernovae and TDEs last only a few months before disappearing. It’s very unusual for something to stay bright for more than two years.”
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According to the study, the actual explosion occurred nearly 8 billion light-years away when the universe was about 6 billion years old and is still being detected by a network of telescopes.
AT2021lwx was first detected in 2020 by the Zwicky Transient Facility in California, and was subsequently picked up by the Asteroid Terrestrial Impact Last Alert System (ATLAS) in Hawaii.
But until now, the scale of the blast was unknown.
Last year, astronomers witnessed the brightest explosion ever recorded — a gamma-ray burst known as GRB 221009A.
While this was brighter than the AT2021lwx, it only lasted for a fraction of the time, meaning the total energy released by the explosion of the AT2021lwx was much greater.
Dr Wiseman added that these events could hold the key to understanding how the centers of galaxies change over time.