James Dunlop probably discovered NGC 456 = D 7 = h2399 on 1 Aug 1826 with his 9" reflector and described "a faint round nebula, 35" diameter, with a small star near the south margin, but not involved." D10 is possibly a duplicate observation - the description is similar "an elliptical nebula, about 1' long and 40" broad, with three minute stars in it." and the position is 20' ENE of NGC 456. John Herschel observed this object on at least 3 sweeps from the Cape as the first of 3 nebulous clusters with NGC 460 (observed 4 times) and NGC 465 (recorded once). In addition it appears that h2398, which did not enter the GC or NGC is a 4th observation of h2399 = NGC 456 but with a poor RA. Herschel equated D 7 with h2399.

400/500mm - 18" (7/6/02 - Magellan Observatory, Australia): this is the first of an unusual chain of three nebulous clusters with NGC 460 and NGC 465 within 10'. The best view of the entire group was at 171x using an UHC filter. At 220x the largest in the trio is NGC 456, appearing as a roundish 3' glow with a very small knot embedded in the SE end (SMC-N83A). A few stars are superimposed (Hodge Association 61) on the glow. NGC 460 lies 4' ESE. Visible in 10x30 IS binoculars.

Notes by Steve Gottlieb