AST 2002 Lecture Notes - Lecture 29: Stellar Evolution, Low Mass, Binary Star
Document Summary
Properties of stars: luminosity, temperature, mass. The best way to measure the distance to nearby stars is with stellar parallax. Brightness: apparent brightness how bright does it appear, how many photons are reaching us, absolute brightness luminosity, how much light is it actually giving off, distance is a factor in this; farther away appear dimmer, closer appear brighter. Inverse square law things appear dimmer as you get further away from them; if you go 3 times away it will appear 9 times dimmer: can find how far away the star is. Stellar mass: to directly determine mass, we need an orbiting object, mass determines what happens to a star, stars of the same mass and age will do the same thing, binary star systems. For example, only the hottest stars can ionize helium. Only the coolest stars can have molecules.
