Heinrich d'Arrest discovered NGC 4851 on 21 Apr 1865 with the 11-inch refractor at Copenhagen. His single position is less than 3 sec of time west of CGCG 160-061. This is a close double system (faint companion close northeast), which CGCG labels NGC 4851 + IC 839. But IC 839 = CGCG 160-057, located ~2' southwest of NGC 4851. See Harold Corwin's identification notes.

400/500mm - 17.5" (4/21/90): very faint, very small, elongated N-S. This is a double system oriented SSW-NNE (not resolved) in AGC 1656. IC 839 is a separate galaxy 2.0' SW.

600/800mm - 24" (6/3/19): at 322x; faint, fairly small, elongated SSW-NNE (the orientation of this close pair) but it was difficult to resolve. An offset stellar nucleus was sometimes visible on the south side (brighter galaxy) and possibly a fainter nucleus to the north.

Notes by Steve Gottlieb