Energy Generation in Stars: Sources, Nuclear Fission, Hydrogen, Nuclear Reaction, CNO Cycle
Two Energy sources are available to stars: Gravitational Contraction (Kelvin-Helmholtz) and Nuclear Fusion in the hot core.
Stars
Stars: Useful Basics on Absolute and Apparent Magnitude
Magnitude is a unitless measure of the brightness of a star in a defined passband, often in the visible or infrared spectrum.