Black holes are formed by supernovas, which are huge stars blowing up. (Imagine a bomb blowing up. Then imagine something five octillion time bigger–5,000,000,000,000,000,000,000,000,000 times bigger—That is a small supernova!) A black holes gravity is so strong that even light cannot escape. A dot the size of a period from a black hole can weigh up to 3,000,000,000,000 (three trillion) tons! Black holes can pull anything that comes in its path. However, we do not know what happens when two black holes meet.

There is a theory though, that black holes have a point where all the matter they suck in comes out. This is called a white hole, and some scientists believe that the end of a black hole is another dimension. They also beleive that if the black hole did not have an outer shell (called an event horizon), then the laws of nature could break down. For instance, if the outer shell of one black hole did not exist, then it could organize a huge man in a chicken suit to lay an egg on the sun! It is a strange concept, but according to NASA, all black holes we have found have event horizons. Hope this helps!

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