John Herschel discovered NGC 3010 = h641, along with NGC 3009, on 17 Mar 1828 (sweep 138). He reported it as "F; psbM; r; stars seen. The second of 2 [with NGC 3009]." There is nothing at his position, but 35 sec of RA east and 1.4' south is UGC 5273. His RA for NGC 3009 is also off (to the west), but by only 16 sec, which is strange. Another possibility is that h640 refers to the southwest component of NGC 3010 (MCG +07-20-065 = PGC 28330). If that's the case, the relative offsets would be more in line but still not accurate. Corwin notes that JH's descriptions are generic enough they don’t assist in choosing between these two alternatives. So, he favors leaving the "traditional" identification as is.

The observations at Birr Castle are interesting. The 1861 publication only includes the note "Several knots near NGC 3009 and 3010]. The full account is given in the 1880 monograph. On 1 Mar 1854 R.J. Mitchell recorded, "one pB NGC 3009], 6' f and a little n are two others vF, about 3' apart pf; several others round about". His separations are poor but probably the second part refers to NGC 3010 and one of its companions. Thirty-five years later in 1878, Dreyer made another observation and wrote, "the f one NGC 3010] is smaller and in a rectangular triangle of 3 stars." At least one of these "stars" is likely a galaxy. Hermann Kobold measured accurate positions of the two southern components of NGC 3010 with the 18-inch refractor at Strasbourg.

400/500mm - 17.5" (2/8/91): triple system consisting of two very faint, small, round "knots" (identified as UGC 5273a and 5273b in the UGC) with a separation of 40" oriented SW-NE. The third component UGC 5273c) is 1' NE and appeared as a mag 15.5 "star". NGC 3009 lies 5' WSW.

600/800mm - 24" (3/21/20): at 375x; triple system oriented SW to NE, with the NE member (NGC 3010C) the faintest. It appeared extremely faint, slightly elongated, very low surface brightness, 15"x10". The SW member was fairly faint, fairly small, ~24"x18" SW-NE, very small brighter nucleus and the middle galaxy was fairly faint, small, elongated 3:2 NW-SE, ~20"x14", very small brighter nucleus.

Notes by Steve Gottlieb