ASTR 1150 Lecture Notes - Lecture 6: Triple-Alpha Process, Milky Way, Gravitational Collapse
Document Summary
Astr 1150 - lecture six : leaving the main sequence. He around core gets how enought to fuse. Radiation has to pass through less material. Reaches outer layers of star more easily. Like taking the lid off a pot. Expansion of outer nonburning envelope causes surface temperature to drop. Overall, luminosity increases greatly (due to increased size) Huge increase in diameter offsets lower surface temperature. Star clusters make very nice cmds (colour magnitude diagrams) All stars born around the same time from the same collection of gas and dust (same nebula) All stars in rougly the same region of space. Open star clusters, these are in the disk of the milky way galaxy and have formed recently) Globular star clusters, these live in the halo" of the milky way galaxy and formed billions of years ago - mini galaxies". While h burning shell and nonburning envelope are expanding, he core is shrinking.
