ASTR 152 Lecture Notes - Lecture 9: Giant Star, White Dwarf, Solar Mass
Document Summary
Chapter 10: post main sequence evolution (deaths of stars) Sms and hms: sms/mms solar/medium mass stars . 4 - 4 solar mass, hms high mass stars 8 or higher solar mass. The end of their sequence is when all of the h in their core is converted into he; High mass stars convert sooner than medium mass stars. After this conversion, the outer layers expand and cool, and the he rich core collapses and heats up: solar mass stars more toward red giants, high mass stars more massive ones. Giant stars have low surface temperatures (mostly red), but have high luminosities because they are very large; so large, that mass can be escaping from their surfaces easily, and they lose mass (gases) from their surface. They do so by: stellar wind gas escaping from the sta(cid:396)"s su(cid:396)fa(cid:272)e; like sola(cid:396) (cid:449)i(cid:374)d, (cid:271)ut st(cid:396)o(cid:374)ge(cid:396, p(cid:396)odu(cid:272)i(cid:374)g (cid:862)pla(cid:374)eta(cid:396)y ne(cid:271)ula(cid:863) gas expelled and expanding from a giant star.