Édouard Stephan discovered NGC 3117 = St IX-21 on 15 Mar 1877 and logged "eF, eS, R, stellar nucleus." His position matches UGC 5445.

400/500mm - 17.5" (3/25/95): faint, small, round, 30" diameter, weak concentration to a very small brighter core. A pretty mag 9.5/11 double star at 18" separation lies 8' NNW. Located 6' NW of mag 8.8 SAO 118106.

Notes by Steve Gottlieb