What are Black Holes?
A black hole can be compared to a vacuum cleaner. Just like a vacuum cleaner sucks up all the dirt around it , so does a black hole . It cleans up outer space by taking in debris, using gravity.
How do black holes form?
If a large star has no more fuel, it can’t support its own weight. Then, its hydrogen layers exert pressure on it. So, it gets compressed. Eventually, the star becomes smaller than even an atom.
However, it still has a great deal of mass. So, its gravitational pull increases. Think of what would happen if you squeezed the earth in a jar. Its gravitational pull would be much stronger, because it would be covering a lesser area.
A black hole pulls whatever’s nearby, even light, towards itself. Since light is trapped in it, it appears black.
Kinds of black holes
There are three kinds of black holes in space- Stellar-mass black hole, supermassive black hole and ultramassive black holes.
Stellar-mass black holes
A stellar-mass black hole is formed when a big star (about 10 times our sun’s size) dies, exploding in an extremely bright burst of light.
This light is brighter than a galaxy and is called a supernova. A black hole formed in this way is 3-15 times bigger than our sun.
Supermassive black holes
Scientists are still unsure how supermassive black holes are formed. They are much bigger than stellar-mass black holes. One of them would equal a 100 million suns.
There is a supermassive black hole in the middle of the Milky Way. So, it gets a great deal of matter it can pull. It is called Sagittarius-A. Black holes like these power active galaxies and old ones too, which are called quasars.
Ultramassive black holes
Ultramassive black holes are 10- 40 billion times the size of the sun. This mass can enable it to hold entire groups of galaxies together.
Black Hole Facts
Although scientists have not seen black holes, they have deduced their existence. Things around a black hole suddenly begin moving faster as they come near the black hole.
Black holes star in theoretical concepts like wormholes. These are tunnels that could enable quick movement through both time and space. However, there is no proof of their existence yet.
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