William Herschel discovered NGC 3456 = H IV-29 = h792 on 8 Feb 1785 (sweep 371) and recorded "a small star with an eF brush towards the preceding side, or a vF nebula close to and preceding the star. I perceived it in stopping to gage, otherwise should certainly have overlooked it. 240 shewed the the same." There is nothing at his position, but 40 sec of RA east and 4' further south is MCG -03-28-018 = PGC 32730, and the description applies.

On 16 Dec 1828 (sweep 111), John Herschel wrote, "a *12m with an extremely F neb appendage. At first it seemed to envelope the *; but Mr Dunlop, to whom I showed it, considered it be detached." Based on photographs taken at the Helwan Observatory in 1919-20, it was described as "F, 1.75' x 0.75', E 80°; spiral with sharp nucleus."

400/500mm - 18" (3/29/03): moderately bright and large, elongated 4:3 ~E-W, 1.2'x0.9', brighter core. A mag 13 star is at the NE edge. Located just over one degree ENE of mag 3.1 Nu Hydrae.

Notes by Steve Gottlieb