Dark galaxy

From Wikipedia, the free encyclopedia

A dark galaxy is a galaxy sized object containing no stars (hence 'dark'). It may contain gas, dust and dark matter. Several objects have been suggested to be dark galaxies, but some claims have later been disproved.

Contents 1 Candidates 1.1 HE0450-2958 1.2 HVC 127-41-330 1.3 VIRGOHI21 2 See also 3 References

[edit] Candidates

[edit] HE0450-2958

HE0450-2958 is an unusual quasar as no host galaxy has been detected around it. It has been suggested that this may be a dark galaxy in which a quasar has become active.

[edit] HVC 127-41-330

HVC 127-41-330 is a high velocity cloud between M31 and M33.

[edit] VIRGOHI21

The discovery of VIRGOHI21 was announced in February 2005. It was found by looking for the radio waves emitted by hydrogen. It has now been proven that some dark galaxies contain stars. Therefore a dark galaxy is held together by dark matter alone. So far, no dark galaxy with a black hole as a center have been discovered

[edit] See also

• Low surface brightness galaxy

[edit] References

• Clark, Stuart. "Astronomers claim first 'dark galaxy' find", NewScientist.com news service, 2005-02-23. Retrieved on 2006-10-26.
• Shiga, David (2005-02-26). "Ghostly Galaxy: Massive, dark cloud intrigues scientists". Science News Online 167 (9): 131. Retrieved on 2006-10-26.