A massive black hole appears to have eaten so much that it fell asleep, scientists have said.
It swallowed so much of the mass from its surrounding galaxy that it has gone dormant, researchers said.
It has been left with a huge mass, roughly 400 million times that of our Sun. Its huge size means that it makes up a vast portion of its host galaxy, representing 40 per cent of its mass, compared with the typical 0.1 per cent.
Its huge size meant that it could be spotted so far in the universe that it came from the early time of the cosmos. The black hole was spotted when the universe was only 800 million years old.
Despite its huge size, however, the black hole has now largely stopped eating. It is now swallowing the galaxy around it at just one per cent of its theoretical limit.
That suggests that we might have been wrong about the ways that black holes develop: it was not previously thought that one from so early in the universe would be so big but also now so slowly growing. The most likely explanation is that they are undergoing periods of fast growth and then dormancy, researchers believe.
“Even though this black hole is dormant, its enormous size made it possible for us to detect,” said lead author Ignas Juodžbalis from Cambridge’s Kavli Institute for Cosmology.
“Its dormant state allowed us to learn about the mass of the host galaxy as well. The early universe managed to produce some absolute monsters, even in relatively tiny galaxies.”
A paper describing the findings, ‘A dormant overmassive black hole in the early Universe’, is published in Nature.
