30 Amazing Facts in Science (Download link below)

A : Black holes are extremely compact space objects that were once massive stars. Sometimes a huge star begins to shrink until it is smaller than an atom. This is called a black hole. The centre of the black hole is called ‘singularity’.The gravity near this point is so strong that any object that gets too close to the black hole is pulled into it. Even light gets sucked into it,which is why we can’t see a black hole. Scientists use special instruments to detect a black hole’s presence. They examine the effects it has on the objects near it.