There are actually two types of black holes. One type is Stellar Black Holes, where are a star, 40 or more times the size of our Sun, explodes as a Supernova, leaves a black hole behind. The other is a Supermassive Black Hole. These are between 100,000 and 1 billion times the mass of our Sun. At the center of each galaxy (such as our own Milky Way) is one of these objects. We believe that they started out being Stellar Black Holes and slowly pulled nearby gas and stars into over time, growing in size. This it the current theory, however it is a difficult subject.
marieclaire
There are actually two types of black holes. One type is Stellar Black Holes, where are a star, 40 or more times the size of our Sun, explodes as a Supernova, leaves a black hole behind. The other is a Supermassive Black Hole. These are between 100,000 and 1 billion times the mass of our Sun. At the center of each galaxy (such as our own Milky Way) is one of these objects. We believe that they started out being Stellar Black Holes and slowly pulled nearby gas and stars into over time, growing in size. This it the current theory, however it is a difficult subject.
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