Alternate Definitions for Protostars

A stage in the process of star formation, after the gravitational collapse of the dense pre-stellar core and before the initiation of nuclear fusion in the central object which will eventually become a star. Protostars are classified into four groups: Class 0, Class I, Class II, and Class III.

A stage in the process of star formation, after the gravitational collapse of the dense pre-stellar core and before the initiation of nuclear fusion in the central object which will eventually become a star. Protostars are classified into four groups: Class 0, Class I, Class II, and Class III.