Black Hole is star with gigantic mass, though it is invisible its gravitational pull is so huge even light can not escape from it.

Black Hole: most amazing object in our universe to study and thus unlocking the mysteries of universe

Albert Einstein predicts that there are other types of stars in our universe which we cannot see. They will behave like invisible stars with enormous gravity from which even light cannot escape. As no light can escape we cannot see them. But we can feel their gigantic gravitational pull and magnetic field.

The first history of discovering such a star was a milestone from astronomical and scientific point of view. Scientists have noticed powerful X-rays in a galaxy but they could not see the source. Something was there, something invisible. Whatever it was it has 7 times more mass than our sun. They named it BLACK HOLE. And the story of Black Hole begins.