Life cycle of a star
Every star has a life cycle just like a human or a frog except stars do it on a much larger scale. Stars start life as a massive cloud of matter and then get pulled together to create a star. But stars do not last forever most stars last for millions of years but they still end. When a stars life ends it may explode or implode to create a black hole.
The reason stars even start life and end life is because of nuclear fusion. Nuclear fusion is a reaction where matter is forced together and the nuclei are fused together. This is how the first start was born when hydrogen atoms were fussed together to create helium. After this many more starts and a lot more elements were created.
Stars start there life as a cloud of gas called a nebula. Mainly consisting of hydrogen and helium. The gases will then be drawn to a centre point of gravity which will then create a protostar. And then the nuclear fusion in the core of the star will star and the star will stabilize. This is known as the stars equilibrium when pressure equals gravity.
A star will now move into the main sequence phase this can last up to 50 million years while it still has hydrogen to burn. In main sequence the fusion will reach a high point and this is when a star will shine brightest. Also a star will contact for the loss of fuel. Our star is in the main sequence phase at the moment.
By this point all of the hydrogen in the star has been used but the star will still be able to last on the helium. A Star has also under gone a change in appearance it has now become a red giant. The outer layer of the star has expended to try and cool down the sun. Because helium is fussed at a higher temperature. But there is a lot less helium in the core so this can only last about a million years. But the star is not dead because the last option of any star has been reached. Carbon burning.
Up to this point, most of the events of stellar evolution are well documented. We do know that a...
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