University of Edinburgh

BSL Astronomy Glossary - black hole - definition

Definition: A black hole is formed when a massive star, a supergiant, dies. In the final stages of this process, the star collapses in on itself, becoming smaller and smaller until it is a tiny object. Despite becoming very small, the original mass of the supergiant star remains the same, creating an intensely strong gravitational force, which is so strong that not even light can escape from it.