EAS 1601 Lecture Notes - Lecture 4: Protostar, Molecular Cloud, Main Sequence

• School: Georgia Tech
• Department: Earth and Atmospheric Sciences
• Course: EAS 1601
• Professor: Christopher Reinhard

Document Summary

Eas 1601 thursday, august 27, 2015 lecture 4. Life cycle of stars building the periodic table: (1) the birth of a star core fusion. (a) molecular cloud begins to collapse under its own gravity. (b) as the cloud collapses, it begins to rotate more rapidly and flattens into a disk. (cid:894)(cid:272)(cid:895) e(cid:448)e(cid:374)tuall(cid:455), a (cid:858)protostar(cid:859) (cid:449)ill for(cid:373) at the (cid:272)e(cid:374)ter of the disk. Protostars can form with a wide range of initial masses, and the initial mass strongly controls the rest of the star(cid:859)s life cycle. Protostar stage ends when the temperature and pressure at the center of the protostar become high enough to initiate nuclear fusion. Hydrostatic equilibrium -> a balance is maintained between thermal pressure outward from fusion in the core and inward pressure due to gravity: (2) the life of a star making light elements. Main sequence: the (cid:373)ajor portio(cid:374) of a star(cid:859)s life (cid:272)(cid:455)(cid:272)le.