In the distant universe, a supermassive black hole appears to be devouring a huge cloud of gas, producing an extraordinary explosion the likes of which we have never seen before. So far, it has released about 100 times the total energy the sun will release in its entire lifetime, and counting.
This gigantic hell, called AT20211wx, was first spotted in 2020 by the Zwicky Transient Facility in California. Philip Wiseman at the University of Southampton in the UK and his colleagues made a series of follow-up observations with other observatories in the years that followed. “We see different big explosions and flashes in the universe, but nothing like what we see here,” Wiseman says.
The only cosmic objects brighter than AT20211wx are quasars, which are caused by a continuous flow of gas into a supermassive black hole. This explosion, which increased more than 15 times in the space of about four months and then began to fade steadily, is still ongoing. Observations seem to point to a supermassive black hole devouring a gargantuan cloud of gas, possibly 100 times larger than the solar system or even larger.
These observations could help explain why some relatively small galaxies contain oversized black holes. “We thought we knew the main growth patterns of black holes, but it looks like they might also grow in a different way than we thought, with violent and explosive growth episodes,” Wiseman says.
Further analysis of this object could help elucidate exactly how it works, as well as how black holes behave more generally. “Because it’s so big, shiny, and durable, it allows us to look closely at the inner workings of what happens when matter falls into a black hole,” says Wiseman.