ASTRO-110 Lecture 30: Astro_110_Lecture_30
Document Summary
High mass stars: the interior structure of a high mass star is different from that found in a low mass star. When intermediate and high mass stars have nearly exhausted their hydrogen fuel, they start to move off of the main sequence. When the core"s supply of hydrogen is exhausted, the core contracts and gets hotter. A shell of hydrogen outside the core begins to fuse. this causes outer portions to expand and cool. As the core shrinks and heats, helium fusion begins. in any star with a mass greater than 2m, helium fusion begins gradually. unlike low mass stars ,there is no helium flash. With the renewed core fusion, the core expands, cooling the fusing shell above it. meanwhile, the surface contracts and warms. Intermediate mass stars the cores of the intermediate mass stars never get hot enough for carbon to begin to fuse. their collapse is foiled by electron degeneracy pressure.
