- Black holes
- Not Applicable ()
Black holes are the remnants of stars that ended their lives as supernovae. They are characterised by a region of space in which gravity is so strong that not even light can escape. The boundary of this region is known as the event horizon and, at the centre of the black hole, is the singularity, where the mass of the dead star is compressed to a single point of zero size and infinite density. It is this singularity that generates the powerful gravitational field of a black hole.