Albert Marth discovered NGC 900 = m 57 (along with NGC 901) on 5 Sep 1864 with Lassell's 48" on Malta and logged "vF, vS, stellar". Marth's position matches UGC 1843 = PGC 9079. This galaxy is misidentified as NGC 901 in the MCG (+04-06-020) and the position is 2' too far north.

400/500mm - 17.5" (10/29/94): faint, small, round, 0.4' diameter, even concentration to a small bright core and stellar nucleus. Brighter of a close pair with NGC 901 2.8' NNE. Forms the east vertex of a "cross" asterism with three mag 11-13 stars 2.8' NW, 3.1' SW and 4.5' W. Almost collinear with a bright wide pair of mag 9-10 stars at 32" separation located 7' S.

17.5" (12/23/92): faint, small, round, weak even concentration, small brighter core. A mag 9.5 star is 7.5' S.

Notes by Steve Gottlieb