William Herschel discovered NGC 5103 = H II-665 on 9 Apr 1787 (sweep 725) and recorded "pB, S, E, 300x showed it like a star with pretty strong burs." His position is 8 sec of RA too far west. Engelhardt measured an accurate micrometric position.

400/500mm - 18" (5/30/03): this is a pretty, fairly small spindle-shaped lenticular, elongated 2:1 NW-SE, 0.6'x0.3'. Located 1.8' S of mag 8.2 SAO 44572. A distinctive string of mag 11/12/13 star is to the NE of the bright star. NGC 5123 lies 29' E.

Notes by Steve Gottlieb