Wikipedia:Good articles/Black hole

A black hole is a place in space where gravity is so strong that nothing can escape from it, not even light. Black holes are made when a lot of matter is squeezed into a small space. This idea comes from Albert Einstein's general theory of relativity. The outer edge of a black hole is called the event horizon. When something enters the black hole, it cannot get out. Black holes act like perfect black bodies, which means they do not reflect any light.