Dark galaxy

A dark galaxy is a galaxy whose mass consists largely of non-self- luminous matter and thus contains very few or no stars. Hence the suffix "Dark".

The galaxy could contain gas, cosmic dust, and dark matter. For multiple objects, it was thought they were a dark galaxy, in some but this was later refuted.

Candidates

HE0450 - 2958

HE0450 - 2958 is an unusual quasar, in which no galaxy around him could be found. It was suspected that this might not be a dark galaxy in which a quasar was active.

HVC 127-41-330

HVC 127-41-330 is a high-speed cloud around M31 and M33.

VIRGOHI21

The discovery of VIRGOHI21 was announced in February 2005. It was found, as was sought by radio waves, which are caused by hydrogen.