AST 111 Lecture Notes - Lecture 8: Thermostat, Degenerate Matter, White Dwarf
18 Dec 2020
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Document Summary
The sun"s life expectancy is about 10 billion years, until its core hydrogen is used. The life expectancy of a 10msun star has 10 times as much fuel, but uses it. H to he in their cores are no longer on the main sequence. High-mass star high luminosity, short life, larger radius, blue. Low-mass star low luminosity, long life, small radius, red. Stellar properties depend on both mass and age those that have finished fusing. All stars become larger and redder after exhausting their core hydrogen (giants. Most stars end up small and white after fusion has ceased (white giants) Variable star = any star that varies significantly in brightness with time. Pulsating variable stars = brightness alternately rises and falls (peaks) over a 50 day period. Cepheid variable stars = most pulsating variable stars inhabit an instability strip on the. Hr diagram; the most luminous ones are known as cepheid variables.
