The Sky at Night — Episode 3: Black Holes in Space

You are watching the episode Black Holes in Space What is a Black Hole? Nobody can yet be sure; it may be the final state of a very massive star which has collapsed, surrounding itself with a ' forbidden zone' from which not even light can escape. Patrick Moore discusses these remarkable objects, which have become so important in modern astronomy, with lain Nicolson of Hatfield Polytechnic Observatory.