M85 is a lenticular or elliptical galaxy located in Coma Berenices that's a member of the Virgo cluster of galaxies. At magnitude +9.5 and covering 7.1 x 5.5 arc minutes, it's similar in brightness and size to another Virgo cluster galaxy, M84. Spotting M85 with 7x50 or 10x50 binoculars is challenging and dark skies and good seeing conditions are a must. Small 80mm (3.1-inch) refractors, reveal a featureless ball of fuzz with a slightly brighter core. The view through amateur scopes in no way reflects the true nature of this distant object. It's a large galaxy that's located 60 million light-years away, making it one of the most remote objects in the Messier catalogue. Its actual diameter is 125,000 light-years and it's estimated to contain 400 billion stars. Long classified as a lenticular galaxy of type S0, recent observations have suggested M85 could be an elliptical galaxy of type E1.
Pierre Méchain discovered M85 on March 4, 1781. He reported the discovery to his friend Charles Messier, who subsequently catalogued it on March 18, 1781. On that night, Messier was very active. He discovered another seven galaxies, all of them Virgo Cluster members and also re-discovered bright globular cluster M92.
The main crux of the Virgo cluster lies about halfway along an imaginary line connecting Denebola (β Leo - mag. +2.1) with Vindemiatrix (ε Vir - mag. +2.8). Most of the group members can be found in this region of sky. However, M85 is located at the very northern edge of the cluster, some 6 degrees northwest of the group centre and one degree northeast of star 11 Comae Berenices (mag. +4.7).
It's best seen during the months of March, April and May.
Through medium size 150mm (6-inch) or 200mm (8-inch) scopes, M85 appears as a round diffuse ball of light with a much brighter central core. However, even larger scopes don't reveal much more detail. Also visible in the same field of view as M85 is neighbouring barred spiral galaxy NGC 4392. This galaxy is positioned 8 arc minutes to the east and the pair are currently interacting with each other.
Supernova (SN 1960R) was observed in M85 in December 1960. It peaked at magnitude +11.7. But supernova hunters be warned, there's a foreground star positioned south-southeast of the galaxy nucleus that often tricks many observers.
M85 Data Table
|Lenticular galaxy (or Elliptical galaxy)
|S0 (or E1)
|12h 25m 24s
|+18d 11m 27s
|Apparent Size (arc mins)
|7.1 x 5.5
|Number of Stars