A mysterious blast of light is a black hole pointing straight at Earth, scientists say
A mysterious and incredibly intense blast of visible light that came towards Earth came from a black hole that is pointing straight at us, astronomers have said.
The discovery marks the furthest such event that scientists have ever said, as well as being the first time that astronomers have detected one using visible light. The latter was only possible because the jet is pointing almost directly at Earth.
When stars get too close to a black hole, they are torn to shreds and the blast can be detected throughout the universe. The event is known as a tidal disruption event, or TDE, and in abou 1 per cent of cases they send plasma and radiation out of each side of the black hole.
Those rare events are known as jetted-TDEs, and have been likened to grabbing a toothpaste tube and having material spurt out of either end. Scientists hardly ever see them, and understand even less about how they actually happen.
As part of the effort to better understand them, scientists watch the sky for signs of the events in the hope that they can turn advanced telescopes towards them when they happen. In February, that happened: astronomers saw an intriguing blast of visible light that led scientists to turn some of the world’s most advanced telescopes towards its source.
The light appeared to give off more light than 1,000 trillion suns, and cam out of a part of the sky where no such light had been observed before. That prompted excitement among the scientists who were watching.
Now scientists believe that it comes out of one of those jetted-TDEs, named AT 2022cmc. The jet probably formed when a black hole suddenly started eating a nearby star, shooting energy through the universe – and right at us.
They found that it was coming from incredibly far away, and further away than any other similar event. The light that had reached Earth started on its journey across space when the universe was about a third of the age it is now.
But it was so unusually bright and visible because the jet is pointing right at us, meaning that it is both more intense than usual and can be seen over a broader part of the electromagnetic spectrum.
It led astronomers to discover the TDE, which has already broken a whole host of records. Scientists hope that it can be used to find even more, allowing them to be better understood and give further detail about black holes.
The findings are reported in two new papers. One, ‘A very luminous jet from the disruption of a star by a massive black hole’, is published in Nature; the other, ‘The Birth of a Relativistic Jet Following the Disruption of a Star by a Cosmological Black Hole’, is published in Nature Astronomy.
