Francis Leavenworth discovered NGC 1584 = LM 1-133 (along with NGC 1583 = I-132) on 17 Oct 1885 with the 26" refractor at the Leander McCormick Observatory. Herbert Howe measured an accurate position in 1899-00 using the 20" refractor at Chamberlin Observatory (repeated in the IC 2 notes).

400/500mm - 17.5" (11/10/96): very faint, small, round, 30" diameter, low even surface brightness. Forms a pair with NGC 1584 5.0' SSE. Collinear with a nice well?matched double star 6.5' NE and a mag 13 star 5.0' NE.

Notes by Steve Gottlieb