William Herschel discovered NGC 4588 = H III-98 on 13 Apr 1784 (sweep 191) and recorded "eF, eS. By a misunderstanding the time & number [PD] was not taken; however at 12h 24m the time was marked down, which was less than 1 min after the transit of the nebula; so that the time of the nebula must be about 12h 23m or 12h 23m 30s. The number as far as I can recollect might perhaps be about 40, which gives 45'; but is more uncertain than the time. I saw the nebula very well." Though very possibly a coincidence, WH's rough position is just 2.4' northeast of UGC 7810. In the 1912 revision of WH's catalogues, Dreyer states "It may = IC 3591 or IC 3617. No object on Wolf's plate in the place of NGC 4588."

400/500mm - 18" (3/13/04): faint, fairly small, elongated 2:1 WSW-ENE, 0.8'x0.4'. Observations made through thin clouds.

Notes by Steve Gottlieb