Is There Such Thing As Black Holes?

Yes, they are the remnants of huge stars that exploded and left their cores which were so heavy they pulled anything in their vicinity into them, even light which is why we can't see them. The only way we have of detecting a black hole is by the direct influence it has on objects around it and their orbit. The point of no return is called the "event horizon" this is where there is no escape from it's pull. It's center of gravity or the mas that causes the gravity is called the singularity and can be as small as a pinpoint or as large as many suns. Scientists now believe that their is a super massive black-hole at the center of most galaxies, even our own "Milky Way".

Yes check international astronomy for history of black holes