William Herschel discovered NGC 6173 = H III-640 = h1962 on 18 Mar 1787 (sweep 718) and noted "vF, vS." His position is accurate.

300/350mm - 13.1" (8/5/83): fairly faint, moderately large, brighter core, slightly elongated. A mag 8 star is 9' SE.

400/500mm - 17.5" (7/5/86): moderately bright, moderately large, strong bright core, oval NW-SE. One of the brightest and largest members of AGC 2197. NGC 6174 lies 3.5' N and NGC 6175 11.3' SSE. Located 8.5' NW of mag 7.9 SAO 46127.

Notes by Steve Gottlieb