Stars Flashcards
Main Sequence
- Nuclear reaction taking place in the core (H to He).
- Most stable
How are absorption spectra formed?
- Excite
- Energy jump (Allowed)
- (Fall) Re-emit
Protostar
Very hot, dense sphere of condensing dust and gas that is on its way to becoming a star
Radiation Pressure
Pressure from photons released in the core of the star
Gas Pressure
The pressure of the nuclei from the sta’s core pushing outwards
What masses of stars will become Red Giant?
0.5M to 10M
Planetary Nebula
Outer layers of a red giant have drifted off into space, leaving the hot core behind at the centre as a white dwarf
White Dwarf
A very dense star formed from the core of a red giant, in which no fusion occurs
Electron Degeneracy Pressure
The quantum-mechanical pressure created by the electrons in the core of the collapsing star.
Chandraeskhar Limit
The mass of a star’s core beneath which the electron degeneracy pressure is enough to prevent gravitational collapse, 1.44M
Neutron Star
Remnant core of a massive star after the star has gone supernova and core has collapsed under gravity yo an extremely high density (If >1.44M)
Black Hole
The remnant core of a massive star after it has undergone supernova and core has collapsed so far that for an object to escape it would need a velocity greater than the speed of light.
Therefore nothing can escape.
Luminosity
Total radiant output power by a star
Energy Level
A discrete amount of energy that an electron within an atom is permitted to possess
Emission Line spectra
- Light emitted from excited isolated atoms produces a line spectrum.
- Series of bright coloured lines against a dark background.
