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Revision as of 22:59, 13 January 2006 by 132.205.45.110 (talk)(diff) ← Previous revision | Latest revision (diff) | Newer revision → (diff)The Spiral Galaxy M99 (also known as Messier Object 99, Messier 99, M99, or NGC 4254) is a spiral galaxy in the Coma Berenices constellation. It was discovered by Pierre Méchain in 1781.
The galaxy has a normal looking arm and an extended arm that is less tightly wound. A bridge of neutral hydrogen gas links NGC 4254 with VIRGOHI 21. The gravity from the dark galaxy VIRGOHI21 appears to have distorted M99 and drawn out the gas bridge, as the two galaxy-sized objects have a close encounter, before they go their separate ways. It is expected that the drawn out arm will relax to match the normal arm once the encounter is over.
See also
External link
- Spiral Galaxy M99 @ SEDS Messier pages
- Dark Matter Galaxy? (UniverseToday)
- New evidence for a Dark Matter Galaxy (PPARC - Particle Physics and Astronomy Research Council)