William Herschel discovered NGC 4592 = H II-31 = h1373 on 22 Feb 1784 (sweep 153) and recorded "a nebula; extended from east to west and also towards the north; it is not cometic and seems to be resolvable." JH made a single observation "eF; L; pmE; vglbM." JH made an error precessing the coordinates for the GC, so the published position was 30' too far north. As a result, when Edward Holden found it again on 23 Apr 1881 he reported it as new (#8) in Publ. of the Washburn Observatory, Vol I.

400/500mm - 17.5" (2/28/87): moderately bright, elongated 5:2 ~E-W, moderately large, 3.0'x1.2', weak concentration. Located 1° NNW of beautiful double Porrima = Gamma Virginis (3.6/3.7 at 4").

Notes by Steve Gottlieb