William Herschel discovered NGC 536 = H III-171 = h120 on 13 Sep 1784 (problematic sweep 271) and simply noted "stellar". Objects that were discovered on this sweep (NGC 513, 515, 517, 523, 536, 552, 553, 614) have various offset errors in RA. His position for III-171 is 1.0 min of RA east of UGC 1013. John Herschel made a single observation in Nov. 1827 (sweep 105) and recorded "pB; pL; gbM; the following of two." His position was accurate. Heinrich d'Arrest made 3 observations and mentioned the star involved on the north side.

Analyzing the sweep data, Harold Corwin suggests H III-171 applies to NGC 529, which is 1 min 40 sec of RA west of WH's place, but Wolfgang Steinicke argues that III-171 must apply to NGC 536 (coming from the previous object NGC 537 in the sweep).

300/350mm - 13" (12/22/84): fairly faint, very small, elongated ~E-W, very small faint core.

400/500mm - 17.5" (8/31/86): moderately bright, slightly elongated WSW-ENE. A mag 14 star is involved at the north edge. Located 8' NNE of mag 6.3 SAO 54695. Brightest along with NGC 529 in HCG 10 with NGC 529 8.5' W, NGC 542 2.6' SE and NGC 531 3.1' NNW.

Notes by Steve Gottlieb