Stars Flashcards
Planet definition
dwarf an object in orbit around a star with
- mass large enough for its own gravity to give it a round shape
- no fusion reactions
- has cleared its orbit of other objects
dwarf planets
have not cleared their orbit of other objects
asteroids
objects too small to be planets, usually in near-circular orbits around the sun and without ice present in comets
planetary satellites
a body in orbit around a planet
comets
small irregular bodies made of ice and dust + small pieces of rock. all comets orbit the sun.
galaxies
collection of stars and interstellar dust and gas.
when do stars begin main sequence
when they are low on hydrogen
what stars evolve into red giants
between 5 o - 10 o ( solar mass)
pauli exclusion principle
2 electrons can’t exist in the same state
electron degeneracy pressure
pressure created when core of star begins to collapse under gravity and electrons are squeezed together creating pressure which prevents core from further collapse.
Chandrasekhar limit
max mass of a stable white dwarf . electron degeneracy only sufficient to prevent collapse if core has mass less than 1.44 Mo