| NGC 4651 | |
| Epoch: | J2000 |
| Type: | SA(rs)c[1] |
| Dist Ly: | 72.0 Mly |
| Z: | 788 ± 2 km/s |
| Appmag V: | 11.39 |
| Size V: | 4.0 × 2.6 |
| Constellation Name: | Coma Berenices |
| Names: | UGC 7901, PGC 42833 |
NGC 4651 is a spiral galaxy located in the constellation of Coma Berenices that can be seen with amateur telescopes, at a distance not well determined that ranges from 35 million light years[2] to 72 million light years.[3]
This member of the Virgo Cluster, located on its outskirts,[4] is known as the Umbrella Galaxy due to the umbrella-shaped structure that extends from its disk to the east and that is composed of stellar streams, being the remnants of a much smaller galaxy that has been torn apart by NGC 4651's tidal forces,[2] [5] something that explains why NGC 4651 has been included on Halton Arp's Atlas of Peculiar Galaxies as Arp 189 -galaxy with filaments-.
Studies using radiotelescopes of the distribution of its neutral hydrogen show distortions on NGC 4651's outer regions and a gas clump associated with a dwarf galaxy that may have born in the event that produced the mentioned stellar streams.[6]
Unlike most spiral galaxies of the Virgo Cluster, NGC 4651 is rich in neutral hydrogen, also extending beyond the optical disk,[6] and its star formation is typical for a galaxy of its type.[4]
Two supernovae have been observed in NGC 4651: SN 1987K (type II, mag. 15),[7] and SN 2006my (type II, mag. 15.3).[8]