John Herschel discovered NGC 3539 = h825 on 13 Apr 1831 (sweep 343) and simply noted "eF". Based on a plate taken with the 24-inch Yerkes reflector, Hubble described NGC 3539 as "F, E 5°, 60"x20"." (1917 PhD thesis).

400/500mm - 17.5" (4/22/95): very faint, fairly small, very elongated 3:1 N-S, 0.6'x0.2'. Contains a small bright core with very faint extensions. NGC 3536 lies 12.3' SSW. Member of AGC 1185.

Notes by Steve Gottlieb