William Herschel discovered NGC 5173 = H III-672 = h1614 on 12 May 1787 (sweep 734) and recorded "eF, vS, stellar, 300 verified it." JH made two observations under h1614 and called it (sweep 255) "pF; R; vsbM; almost stellar." But he assumed it was a new discovery, confusing this object with NGC 5169 = h1611, which is did discover!

400/500mm - 17.5" (5/19/01): moderately bright, round, 1.2' diameter, even moderate concentration to a small bright core and stellar nucleus. Situated at the midpoint of the shorter base of a isosceles trapezoid consisting of four mag 13 stars. Forms a pair with NGC 5169 5.5' NW. Located 39' SSW of M51 and 19' WSW of NGC 5198.

Notes by Steve Gottlieb