Frank Muller discovered NGC 554 = LM 2-305, along with NGC 555 and 556, in 1886 with the 26" refractor at Leander McCormick Observatory. His position is 0.4 min of RA too far west. Herbert Howe measured an accurate position in 1899-00 using the 20" refractor at Chamberlin Observatory (repeated in the IC 2 notes). This is an extremely close double system (PGC 5412 and 5413), with the two components identified as NGC 554A and 554B in NED and NGC 554 and 554A in PGC.

400/500mm - 17.5" (11/6/93): faint, small, round. Forms the SW vertex of an equilateral triangle with a mag 13.2 star 1.8' NE and a mag 12.8 star 1.8' E. Forms a close pair with NGC 555 2' S.

600/800mm - 24" (12/6/18): at 260x; fairly faint, fairly small, elongated 4:3 N-S, ~30"x24". Contains a very small brighter core/nucleus. A mag 12.3 star is 1.8' E. Brightest in a small triplet with NGC 556 1.8' NNE and NGC 555 2.3' SSW. NGC 554 is a merged pair (not resolved) with the two nuclei separated by only 5"-6".

Notes by Steve Gottlieb