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	Black Holes
	Most scientists believe that there is a black hole in the center of our very own Milky Way.

Black holes were once massive stars that used up all their fuel. As they died out, they collapsed inward due to the pull of their own gravity. The gravity of a black hole is so powerful that not even light can escape its pull! Once any matter falls into a black hole, it disappears from the visible universe. It is very hard to see a black hole. Any object that gets too close to a black hole will be pulled inside it. We only know they are there because of the effects they have on other objects that are near them. Any object, whether some dust, or a star, or anything, that gets too close to a black hole will be pulled inside it. As the objects fall toward the black hole, they heat up and get very hot. Scientists can use special instruments to detect the heat the objects give off. That is how we know the black hole must be there.

A Question How do we know that there really are black holes?