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__Life cycle of a low mass star__

♥ All stars are formed from a giant cloud of hydrogen gas, know as Nebula. The gas collapses inwards due to the force of gravity, as the gas collapses it heats up due to friction. The cloud then becomes a Protostar, which many people call a 'Young Star' or 'Baby Star'. It can be described as a spherical, hot object.



In big protostars, over many years there will be enough heat for the hydrogen atoms in the star to fuse together, the result of this is the gas Helium. This process is know as Nuclear Fusion and the star begins to shine.

♥ Once the star is shining, with lots of hydrogen the star then stays in a stable condition. As the star shines, it burns hydrogen,and can remain stable for billions of years.



Once the star has burnt most of it's hydrogen, it's cores nuclear processes then stop. Without the pressure of the core working against gravity, the outer layers of the star begin to collapse inward to the core. The temperature and pressure of the core increases and helium fusion begins. The star is now burning helium, and the star 'swells' up to as much as 100 times bigger than it was before. We call this a Red Giant. This process will last a few million years.

♥ If the star has a low or medium mass, it will die. It will shed the outer layers to form a Nebula cloud once again and will leave behind a hot core, know as a White Dwarf.



The process will begin again when a giant hydrogen cloud collapses under the force of gravity...