A black hole is a fascinating and mysterious astronomical body. It is so-called because it gives off no light and sucks in whatever matter and energy that comes near it. It is the end product left behind after the death of a very massive star.
All stars have a life-cycle — they are born, grow old and finally die. The way they end up depends on the mass they start with. If the star is very massive — more than 30 times as massive as the sun, the end comes in a blinding explosion known as supernova. After the explosion what is left behind is a tiny object called black hole. The gravitational field on a black hole is so strong that it does not allow even light to escape. Thus, a black hole cannot be seen. However, astronomers locate black holes by the gravitational and other effects they have on nearby stars.
