The Lives of Stars
We think we have a pretty good idea of the evolution of single stars.
This understanding has come about as a result of observations of the
color and magntitude of stars as well as using computer models of
stellar evolution.
Stars go through distinct phases of birth, maturity, death, and rebirth.
A star begins as a collpasing cloud of gas in the interstellar medium.
Eventually the core of the star undergoes nuclear fusion and the star
finds itself on the main sequence.
After a few hundred million to a few billion years, the star becomes a
red giant. If the star is a low mass star, the outer layers of the
star release gas forming a planetary nebula at its envelope and a
white dwarf at its core. If the star is a high mass star, the star
explodes as a type II supernova and
leaves behind a neutron star or black
hole.
Areas of current research
- Binary stars
- The vast majority of stars are binary stars. In this stars it is
possible for the evolution of one star to affect another.
- Mass loss
- Stars (especially high mass stars) can lose enough mass to affect the
evolution of the star. How much mass is being lost by the star?
- Convection
- How do you simulate convection in your computer code?
Joseph Wang (joe@athena.mit.edu) (1993-09-15)