Heinrich d'Arrest discovered NGC 582 on 9 Aug 1863 with the 11-inch refractor at Copenhagen. He mentioned the mag 12-13 star that precedes by 4.5 seconds of time and measured an accurate position.

400/500mm - 17.5" (12/23/89): fairly faint, fairly small, very elongated 3:1 SW-NE, weak concentration. Pair with NGC 579 8' NNW.

Notes by Steve Gottlieb