William Herschel discovered NGC 4278 = H I-90 = H II-322 = h1186 on 13 Mar 1785 (sweep 387) and recorded II-322 as "Three [with NGC 4283 and 4286], all in a row, but of unequal size and brightness. The most following [NGC 4286] vF." His single position is 14 sec of time following NGC 4278. He found NGC 4278 again a month later (11 Apr), assumed it was new and recorded I-90 as "Two [with NGC 4283], the time is that of the brightest and preceding [NGC 4278], which is cB, pL, nearly R. The other is sf, pB, S, about 6' distance." JH made two observations and measured an accurate position.

400/500mm - 17.5" (4/25/98): bright, roundish, fairly large, the outer halo increasing to ~3.5' diameter with averted vision. The halo surrounds a well-defined very prominent core which increases to a quasi-stellar nucleus. Forms a pair with NGC 4283 3.5' NE. Poor transparency.

Notes by Steve Gottlieb