John Herschel discovered NGC 7539 = h2217 on 17 Aug 1828 and recorded "F; S; R: psbM; 12"." His single position is very accurate.
400/500mm - 17.5" (9/23/89): fairly faint, fairly small, elongated NW-SE, small bright core, stellar nucleus, diffuse elongated halo.
Notes by Steve Gottlieb