Albert Marth discovered NGC 7783 = m 591 = Sf 99 on 9 Sep 1864 and noted "F, S, lE." His position matches MCG +00-60-058 = HCG 98A, although he apparently missed HCG 98B, attached at the southeast end or thought it was a single object. Truman Safford independently discovered this galaxy on 23 Oct 1867 using the 18.5-inch Clark refractor at the Dearborn Observatory, and also measured an accurate position.

400/500mm - 17.5" (9/7/96): fairly faint, fairly small, elongated 3:1 WNW-ESE, 1.1'x0.4'. Seems brighter on the west end. Brightest member of three viewed in HCG 98 and merges with NGC 7783B = HCG 98b on the SE end [35" between centers]. Located just 1.8' S of a mag 9 star. HCG 98B is very faint, very small, elongated 2:1 NNW-SSE, 20"x10". There is a slightly darker gap where the galaxies are attached. HCG 98C, just 1.8' SE is extremely faint and small, round. At first, I thought it was the mag 15.5-15 star about 25" N. After careful viewing I could see there were two distinct objects here although the star and galaxy were very difficult to view simultaneously.

17.5" (11/6/88): fairly faint, small, elongated WNW-ESE, weak concentration. Forms a contact pair with NGC 7783B = HCG 98B at the SE end. HCG 98B is faint, very small, slightly elongated NW-SE. The pair is situated 1.8' S of mag 9 SAO 128452.

900/1200mm - 48" (10/25/14): at 610x; HCG 98A, the largest and brightest in the quartet, appeared bright, elongated 5:2 WNW-ESE, moderately large, ~1.0'x0.4', small bright core. A star (mag 15-16) is at the ESE tip. Forms a near contact pair with HCG 98B, just southeast of the star.

HCG 98B appeared moderately bright, small, elongated 3:2 NNW-SSE, 21"x14", small brighter nucleus. Located 1.8' S of mag 9.4 HD 223975. The halo of 98A and 98B are fully merged on the SDSS image. HCG 98C, 1.3' SSE of HCG 98B, appeared fairly faint, small, slightly elongated NNW-SSE, 15"x12". A mag 15.5 star is 0.4' N. SDSS J235412.56+002113.3, an extremely faint galaxy (V = 18.0) is just 21" SW. HCG 98D is very faint, round,10" diameter. low even surface brightness. The faintest member in the HCG 98 quartet is located 40" N of NGC 7783 and 1.1' S of a mag 9.4 star that hampers viewing.

Notes by Steve Gottlieb