Lifecycle of a Star
Makaya J
Definition of a Star
A star is a glowing ball of gas that produces energy and is held together by gravity. It grows and develops throughout its lifetime and has many different stages of life.
First Stage
Stars are born within a cloud of dust. They start out as a nebula which is hydrogen and helium dust in space.
Second Stage
The dust collapses under its own gravitational pull and the material in the center heats up. This is now called a protostar which is a hot core in the middle of a collapsing cloud. As the prostars get bigger they attract more atoms into their clump until they form a star.
Third Stage
Stars are fueled by the nuclear fusion of hydrogen which is the process of making one heavy nucleus form two smaller nucleuses. The outflow of energy from the middle of the star make it so the stars won't collapse under its own pressure.
Fourth Stage
When a star uses up all its hydrogen in its core the nuclear reactions stop. Since it doesn't have the energy production needed, the core starts to collapse in on itself and becomes much hotter. Since there is still hydrogen outside of core hydrogen fusion still continues on the outer part of the star. From the rise in temperature the core pushes its outer layers forward making them expand and cool down. This then turns into a red giant.
Fifth Stage
After the star puffs out all of its layers it shrinks down to become a white dwarf. The white dwarf cools and becomes invisible, and after billions of years they run out of fuel. The stars try to stay alive by burning different fuels, but that doesn't work for long so they blow themselves up in a supernova explosion. It outshines all the other stars for about a week then fades away.
Sixth Stage
All that is left is a neutron star. If the neutron star is big enough the core of it collapses and it becomes a black hole. The elements that were inside the super giant such as oxygen carbon and iron scatter throughout space and overtime the stardust creates new stars and planets.
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Sources
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