AST201H1 Lecture Notes - Lecture 13: Stellar Evolution, Main Sequence, Dimeter
![AST201H1 Full Course Notes](https://new-docs-thumbs.oneclass.com/doc_thumbnails/list_view/2407405-class-notes-ca-utsg-ast201h1-lecture12.jpg)
24
AST201H1 Full Course Notes
Verified Note
24 documents
Document Summary
All on the main sequence burn hydrogen in their core (check slides for image) There are also luminosity classes, so with the spectral type, you basically have all you need to know about a star a combinaion of the two is the morgan-keenan (mk) classiicaion. With this we have temperature (obafgkm), and a size/luminosity chart (i to v and wd) Giants: typically 10-15 imes diameter of sun, just within size of mercury"s orbit. As they are no longer fusing hydrogen in their cores. They"re large, with lower temperatures, but they"re huge so very luminous and easy to see. Very very hot, but iny so very low luminosity. Final stage of stellar evoluion, ater the giants. No fusion taking place at all, just residual heat from earlier stages. Last for billions of years, but very hard to see. Stars spend almost enire life on the main sequence. Stop burning hydrogen = when these stars leave the main sequence.