ASTR 100Lgx Lecture Notes - Lecture 24: Zeeman Effect, Chromosphere, Red Giant
Document Summary
The sun has a luminosity of 3. 9 x 1033 ergs per second. The next closest star is 300,000 times away. Due to surface temperature our sun is classified as a g2v star. Average surface temperature of 5800 k (20 times hotter than earth) In 5 billion years it"s gonna go red giant, then shrink to a white dwarf. The sun occupies 0. 5 of a degree in the sky. The sun is larger than 95% of the stars in our portion of the milky way. Extra-solar or exo-solar planets are planets around other stars. Average density of 1. 41 g/cm3, about the same density of jupiter. The sun has differential rotation, once every 25 days at equator but 35 days near poles. It emits energy in all portions of the electromagnetic spectrum. We get a solar constant rate of energy from the sun, 1,380 watts/m2. Luminosity is the total rate at which a star releases energy in all directions.
