Astronomers may have seen witnessed for the first time light from the merger of two black holes. More specifically, a supermassive black hole surrounded by a disk of gas and within this disk are two smaller black holes that could have merged together to form a new one. Typically when two black holes spiral around each other and eventually collide, they send out gravitational waves, which are invisible to telescopes and other light-detecting instruments used by astronomers. Read more for a video about black hole collisions and additional information.
Theorists concocted several ideas about how a black hole merger could produce a light signal by causing nearby material to radiate. Now, they are using Caltech’s Zwicky Transient Facility (ZTF) located at Palomar Observatory near San Diego to search for such a scenario. If one of these events is confirmed, it would be the first known light flare from a pair of colliding black holes.