The Composition of Stars

Absolute magnitude is a measure of the brightness of a star, while apparent magnitude is how bright a star appears from Earth. Luminosity is the amount of radiation a star puts out in a certain amount of time.  Generally, stars with larger masses have greater luminosities. In this topic, you explored how scientists study stars using these characteristics. In addition, you learned how stars are classified into seven different spectral classes. The spectral classes are based on the stars characteristics. The Sun is classified as a G-type main-sequence star, which is yellow in color. This type of star is rather common.