William Herschel discovered NGC 4589 = H I-273 = h1374 on 22 Nov 1797 (sweep 1064) and logged "vB, R, mbM, 3 or 4' dia." His position is 4.5' southeast of UGC 7797. JH made 4 observations, recording on sweep 348 "B; R; pgmbM; 30"; a S * np; dist 1'." His position on this sweep was very accurate.

400/500mm - 18" (5/8/04): bright, fairly large, elongated ~4:3 E-W, 2.5'x2.0'. Sharply concentrated with a very bright prominent core and a fainter halo. A mag 13 star is at the west edge of the core. Forms a pair with NGC 4572 7.5' NW and NGC 4648 lies 22' NE. A wide mag 8/10.5 double at 24" lies 17' NE (in the field with NGC 4648).

Notes by Steve Gottlieb