Supermassive black hole and accretion disc, illustration. A black hole is formed when a massive object collapses under the force of its own gravity, increasing the gravitational pull to the point where, beyond a boundary known as the event horizon, nothing, not even light, can escape. Here, the thin disc of rotating material is the remains of a Sun-like star which was ripped apart by the tidal forces of the black hole. Shocks in the colliding debris, as well as heat generated in accretion, result in bursts of light that resemble a supernova explosion. Image published in 2016. |