William Herschel discovered NGC 2110 = H III-448 = H III-450 = h370 (equivalence noted by Albert Marth in AN 995) on 5 Oct 1785 (sweep 458) and recorded III-450 as "eF, vS, 240 confirmed it." His summary description from three observations reads, "vF, S, R, resolvable, lbM." He also found it on 24 Feb 1786 (sweep 529) and logged "eF, E, er. Is probably a patch." Because of the differing descriptions, WH assumed it was new, and catalogued it again as III-510. On 8 Jan 1831 (sweep 318), John Herschel logged, "vF; R; psbM." and combined the two H-designations in the GC. The declination given in the RNGC is 10' too far north.

400/500mm - 17.5" (1/23/93): fairly faint, fairly small, slightly elongated 4:3 N-S, evenly increases to bright middle and small bright core with a stellar nucleus. Located in a rich star field 6' SSW of mag 8.9 SAO 132606. Mag 5.4 55 Orionis lies 12' WSW. Appears brighter than 14p. Incorrect declination in the RNGC 10' too far north.

Notes by Steve Gottlieb