Édouard Stephan discovered NGC 906 = St X-5 on 30 Oct 1878 with the 31" reflector at the Marseille Observatory and recorded "eeF, irregular oval; dia = 45 arcsec". His position matches UGC 1868 = PGC 9188. Except for NGC 898 and NGC 923 (discovered by WH), Stephan discovered all the NGC galaxies in the cluster on the same night.

300/350mm - 13.1" (10/20/84): fairly faint, small, round. Located in the core of AGC 347 with NGC 909 3.5' S.

13.1" (11/13/82): faint, furthest north in the string of galaxies.

600/800mm - 24" (11/23/19): at 375x; fairly faint, round, relatively large, 50" diameter, diffuse halo, slightly brighter core/nucleus. Located in the core of AGC 347 with NGC 909 3.5' SSE and NGC 911 9' SSE.

Notes by Steve Gottlieb