The hypothetical end point of evolution for a degenerate
star, either a white dwarf or a neutron
star, after it has cooled down to the extent that it can no longer shine,
even dimly. A black dwarf is composed of cold, degenerate
matter – degenerate electron matter (in the case of a white dwarf)
or degenerate baryon matter (in the case of a neutron star). It's thought
that about a trillion years are needed for a star to cool to the point at
which it becomes a black dwarf. Hence, it will be a long time before the
universe contains any such objects.
|Concept art of a black dwarf against a background
field of stars. Art © David Darling
Black dwarfs are not to be confused with black
holes or brown dwarfs.
• TYPES OF STAR