AST 111 Lecture Notes - Lecture 11: Helium Flash, Runaway Greenhouse Effect, White Dwarf

• School: Tunxis Community College
• Department: Astronomy
• Course: AST 111
• Professor: Reynolds

Document Summary

Apparent brightness: how bright stars look in our sky, the amount of power reaching us per unit area. Luminosity: the total amount of power that a star emits into space. Inverse square law for light: apparent brightness = (luminosity / (4pi x distance^2)): means doubling the distance to a star would decrease its apparent brightness by a factor of 4. In stellar parallax, measuring angle p, or the parallax angle, will help us calculate the star"s distance. The smaller angle p is, the farther away the star is. Stars are categorized into spectral types using their spectral lines. Categorized into lettered categories (in order from hottest to coolest): o b a f g. Letters are further broken into numbers (o1, o2, o3, etc. K m (oh be a fine guy, kiss me) the cooler the star. We can use newton"s version of kepler"s third law to measure masses of binary star systems.