When material nears the black hole, it compresses down to form a thin accretion disk.
“We’ve demonstrated that, if you’ve seen one black hole, you’ve seen them all, in a sense,†says Pasham.“People have known this cycle to happen in stellar-mass black holes, which are only about 10 solar masses.Besides being really cool, these observations are only the second time that astronomers have caught the formation of a corona around a black hole.“A corona is a very mysterious entity, and in the case of supermassive black holes, people have studied established coronas but don’t know when or how they formed,†Pasham says.