Black holes hide behind a wide surface called the Event Horizon. Not even light can escape a black hole’s gravitational force. The more massive the object, the bigger the curve hence the more gravity it exerts.At their core, black holes are points where spacetime curves infinitely. Judging by the number of stars massive enough to collapse into a black hole, scientists believe there may be billions of black holes in our galaxy alone. The Milky Way contains a “few hundred million” stellar black holes and a supermassive black hole at its center called Sagittarius A*.