William Herschel discovered NGC 3303 = H III-66 = h730 on 21 Mar 1784 (sweep 181) and recorded "vF, S, E, r. 240 showed it no better than 157, though larger." John Herschel made two observations and measured an accurate position.

400/500mm - 17.5" (3/1/03): faint, moderately large, elongated 4:3 N-S, 1.0'x0.8', broad concentration to a slightly brighter core but no nucleus. Overall fairly low surface brightness.

900/1200mm - 48" (2/19/12): Arp 192 is a highly disturbed double system with a enormous irregular plume to the south and diffuse haze off the east side. At 488x, the size of the main body was ~1.0'x0.7', extended NNW-SSE and split into two components. LEDA 93104 is a large knot with a stellar center on the northwest side of the main core. It is likely the core of an interacting companion. The plume or tail was visible as a diffuse, fairly wide extension attached at the south-southeast end and extending south for ~1.0', roughly doubling the length of the galaxy. A mag 15 star lies 1.6' S.

Notes by Steve Gottlieb