00:00Supermassive black holes. They're pretty big. It's right there in the name. And in galaxy clusters like Abel 2261, there should be a black hole at the center between 3 and 100 billion times the size of our sun. But there isn't one. And scientists believe it's either evading detection due to some mix of starlight and instrumental mishap. Or perhaps more excitingly, it may have been kicked out of the galaxy cluster by some currently theoretical means.
00:27When black holes merge, they send waves of gravitational force across space time. And experts theorize that if those waves were considerably more powerful in a particular direction, that gravitational recoil could kick a black hole in the opposite direction.
00:39So recently, a team of researchers from the University of Michigan looked closer at Abel 2261 using the Chandra X-ray Observatory. They found that the hot gas density decreased the closer their observations got to the galactic core, meaning the area around the core was more dense than the core itself.
00:54But they found no X-radiation, which you would expect from a black hole. So either the black hole is there, but dormant and not feeding, or indeed it was kicked out of the cluster altogether and may still be found elsewhere out in space.
