Heinrich d'Arrest discovered NGC 3994 on 6 Apr 1864 with the 11" refractor at the Copenhagen Observatory. His position, measured on 3 nights, is accurate and he accurately placed a mag 15 star (called 17th magnitude) the precedes by 4 seconds due west.

400/500mm - 17.5" (2/24/90): moderately bright, small, elongated 2:1 SSW-NNE, prominent core. Second of three elongated systems with NGC 3991 3.8' NNW and NGC 3995 1.8' NE. Located 5' WNW of mag 6.4 SAO 62774.

600/800mm - 24" (5/25/14): at 375x appeared fairly bright, elongated oval 5:2 SSW-NNE, 0.8'x35', well concentrated with a very bright core. Second in a striking trio (KTG 39) with NGC 3995 1.9' NE and NGC 3991 3.8' NNW.

Notes by Steve Gottlieb