What characteristics define a black dwarf star?

By definition, a black dwarf is a former white dwarf that has cooled to invisibility. They do not exist yet. No white dwarf stars have cooled enough to be considered black dwarfs. The coolest white dwarf stars known are at temperatures of 3900 K. read more

By definition, a black dwarf is a former white dwarf that has cooled to invisibility. They do not exist yet. No white dwarf stars have cooled enough to be considered black dwarf s. The coolest white dwarf stars known are at temperatures of 3900 K. read more

The name "black dwarf" has also been applied to substellar objects that do not have sufficient mass, less than approximately 0.08 M ☉, to maintain hydrogen-burning nuclear fusion. These objects are now generally called brown dwarfs, a term coined in the 1970s. read more

In theory, white dwarfs will eventually stop emitting light and heat and become black dwarfs. Credit: NASA and H. Richer (University of British Columbia). The last stage of stellar evolution is a black dwarf. read more