William Herschel discovered NGC 3941 = H I-173 = h1005 on 19 Mar 1787 (sweep 719) and recorded "vB, R, NM but very gradually diminishing about 2 1/2' diam." His position (CH's reduction) is 3' too far north. JH made three observation and measured a more accurate position. Samuel Hunter, observing with LdR's 72" on 17 Apr 1862, questioned if it was a "right-handed spiral?"

400/500mm - 17.5" (4/6/91): bright, fairly small, elongated 2:1 N-S, 2.5'x1.2', high surface brightness, small very bright mottled core, substellar nucleus, fairly small halo. A mag 13.5 star is 1.6' ENE of center.

600/800mm - 24" (2/15/18): at 200x; bright, fairly large, elongated 3:2 N-S, ~2.5'x1.8'. Sharply concentrated with an intense core. At 375x the core increases to a very small, quasi-stellar nucleus. Type Ia SN 2018pv (discovered on 3 Feb at the pre-max stage) was easily visible at 13th magnitude, but located only 4" E of center, right up against the edge of the bright nucleus.

Notes by Steve Gottlieb