If the clump is massive enough, it will evolve into a main sequence star.
1.In a cold, dark nebula, gas atoms and dust particles move so slowly that gravity can pull them together.
2. Gas and dust begin to condense into clumps, forming the cores of protostars.
3. As the cores condense, their density and temperature increase.
4. Protostars continue to heat up and accrete matter from nebula. They begin to glow to their increasing temperature.
5. Temperature at the center of a protostar becomes sufficiently high. Thermonuclear fusion of hydrogen into helium begins. The star is officially in the main sequence at this point. The mass that is continuing to fall on to the star forms an accretion disk.
6. In the T Tauri stage, the young star ejects mass into space in a bipolar outflow. A stellar wind blows away the remaining parts of the nebula that surround the star, exposing the star to space.
7. The ejected mass can induce a shockwave in the surrounding interstellar material, triggering formation of other stars.
Processes that cause the star to lose or gain mass come to an end, and the star stabilizes as a main sequence star in hydrostatic equilibrium. The remnants of the accretion disk may remain as proto-planetary disk, from which a system of planets may form around the star. (But i thought all the stuff just got blown away by the stellar wind?!)
No comments:
Post a Comment