Black holes

Black holes form when a body in the Universe has gravity so strong that it pulls in everything around it, even light, which is why a black hole appears black. They can range in size, from the size of an atom to supermassive black hole like the one at the centre of our Milky Way, which has the mass of 4 million suns and is the size of a few million Earths. This means the one thing black holes all have in common is that they are very, very dense.

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