Messier 85
Galaxy in the constellation Coma Berenices
From Wikipedia, the free encyclopedia
Messier 85 (also known as M85 or NGC 4382 or PGC 40515 or ISD 0135852) is a lenticular galaxy, or elliptical galaxy for other authors,[4] in the Coma Berenices constellation. It is 60 million light-years away, and has a diameter of about 36.99 kiloparsecs (120,600 light-years) across.[1][5]
| Messier 85 | |
|---|---|
Galaxy Messier 85 by Hubble Space Telescope | |
| Observation data (J2000 epoch) | |
| Constellation | Coma Berenices |
| Right ascension | 12h 25m 24.0528s[1] |
| Declination | +18° 11′ 27.888″[1] |
| Redshift | 729 ± 2 km/s[1] |
| Distance | 60 ± 4 Mly (18.5 ± 1.2 Mpc)[2] |
| Apparent magnitude (V) | 9.1[3] |
| Characteristics | |
| Type | SA(s)0+ pec[1]/E2[4] |
| Size | 36.99 kiloparsecs (120,600 light-years)[1][5] (diameter; 2MASS total aperture) |
| Apparent size (V) | 7′.1 × 5′.5[1] |
| Other designations | |
| NGC 4382, UGC 7508, PGC 40515[1] | |
Pierre Méchain discovered M85 in 1781. It is within the outskirts of the Virgo Cluster, and is relatively isolated.[6]
Properties
M85 is extremely poor in neutral hydrogen[7] and has a very complex outer structure with shells and ripples that are thought to have been caused by a merger with another galaxy that took place between 4 and 7 billion years ago,[7] as well as a relatively young (<3 billion years old) stellar population on its centermost region, some of it in a ring, that may have been created by a late starburst.[8] Like other massive, early-type galaxies, it has different populations of globular clusters. Aside from the typical "red" and "blue" populations, there is also a population with intermediate colors and an even redder population.[6] It is likely transitioning from being a lenticular galaxy into an elliptical galaxy.[6]
While indirect methods imply that Messier 85 should contain a central supermassive black hole of around 100 million solar masses,[9] velocity dispersion observations imply that the galaxy may entirely lack a central massive black hole.[10]
M85 is interacting with the nearby spiral galaxy NGC 4394, and a small elliptical galaxy called MCG 3-32-38.[11]
Compared to other early-type galaxies, M85 emits a relatively smaller proportion of X-rays.[6]
Novae and Supernovae
Two supernovae and one luminous red nova have been observed in M85:
- SN 1960R (Type Ia, mag. 13.5), was discovered by Howard S. Gates on 20 December 1960,[12] and independently discovered by Leonida Rosino on 18 January 1961.[13]
- M85 OT2006-1 was discovered on the outskirts of the galaxy, by the Lick Observatory Supernova Search (LOSS) on 7 January 2006. It was classified as a luminous red nova, the first to be identified as such.[14]
- SN 2020nlb (Type Ia, mag. 17.436) was discovered by the ATLAS telescope in Hawaii on 25 June 2020.[15][16] This supernova got as bright as magnitude 12.[17]
