John Herschel discovered NGC 5172 = h1613 on 7 May 1826 and logged "F; R: S; 15"." His mean position (two observations) is accurate.

400/500mm - 17.5" (5/30/92): moderately bright, moderately large, elongated 2:1 ~E-W, 2.4'x1.2', brighter middle, gradually increases to small brighter core, irregular surface brightness. A mag 14 star is off the north side of the core 44" from center. Located 11' NW of mag 7.4 SAO 100597. NGC 5180 lies 14' SSE.

Notes by Steve Gottlieb