Alpha Centauri A
Stages of a Star
STAGES OF A STAR
The Nebula is the first stage of a star's life. It is a cloud of gases made up dust, helium, hydrogen, and other gases.
A protostar is the 2nd stage of a star's life cycle. It is a large mass that is formed by the gas that is contracting. "For a one solar-mass star it lasts about 10,000,000 years." (wikipedia). A protostar isn't hot enough yet for hydrogen fusion to take place. It is usually surrounded by dust and the dust blocks the light so it can be hard to see with the naked eye.
The main sequence is where a star spends most of its life. The Main Sequence is where Alpha Centauri A is in now. This is the 3rd stage of a stars life cycle. Here is information about Alpha Centauri A in this stage of its life.
Constellation~ Centaurus the Centaur
Lightyears from Earth~ 4.37 light-years
Red Giant Star
This is the 4th stage of a star's life cycle. It is a star that is starting to die. If a star's mass is 8M or less than the star will turn into a red giant star. It starts when there is no more hydrogen fusion which means there is no balance between outward and inward pressures. The heat has to expand becuase of how big it is so it is cooler than in the main sequence
A white dwarf is the 5th stage of a star's life. It is formed when most of it's central energy is lost. It is normally the size of a planet. There is no more hydrogen fusion in a white dwarf
A black dwarf is the final stage of a star's life. It used to be a white dwarf but no longer emits light or heat.