Nuclear physics. As a star ages, the fusion of lighter elements into heavier elements changes the composition of the star's core, which in turn affects the dynamics of its interior. Convection patterns change, the core's energy production changes, and so on. This ultimately affects the way a star looks in our telescopes.
The first stage of stellar evolution is nebula.
You can find an overview of stelar evolution in the Wikipedia article entitled "Stellar evolution".
The longest stage of stellar evolution is the main sequence phase.
Helium burning is most durable stage in stellar evolution.
Stellar evolution is the term for the changes a star undergoes during its lifetime.
Nuclear fusion affects stellar evolution by essentially halting all mitosis and miosis that any cells in a stellar evolution could experience, and they stunt the growth of the object.
There is no known role of magnetism in stellar evolution.
Scientist believe that stellar evolution contained only hydrogen and then helium.
The endpoints of stellar evolution are: White Dwarf Neutron Star Black Hole The endpoint is dependent upon birth mass of the star.
Main Sequence
it is the cycle of stellar evolution
Gravity effects stellar evolution by pulling down force on the stars while they are forming. Mass will determine how long the star stays alive and burning.