The brown dwarfs are the “failed stars” of the Universe, having gathered enough mass to ignite some rare-isotope fusion reactions, but not enough to become true stars. But many brown ... Many new stars are presently forming here due to the collapse of gas, which traps the heat from stellar formation. read more
The differences between a brown dwarf after fusion and a white dwarf are mass and composition. A maximum-mass brown-dwarf would use up its deuterium and its lithium, but both are just tiny amounts. It still has all its other hydrogen (H 1). read more
In 1975, Jill Tarter suggested the term "brown dwarf", using "brown" as an approximate color. The term "black dwarf" still refers to a white dwarf that has cooled to the point that it no longer emits significant amounts of light. read more