William Herschel discovered NGC 5004 = H III-305 = h1546 on 13 Mar 1785 (sweep 387) and logged "vF, vS, lE."

400/500mm - 18" (7/1/03): moderately bright, fairly small, slightly elongated ~N-S, 0.7'x0.5', well concentration with a very small bright core. NGC 5004A = UGC 8259 lies 3.5' S' and appeared very faint, fairly small, elongated 2:1 ~N-S, 0.6'x0.3', low even surface brightness. A mag 12 star is just off the SE tip, 45" from center. IC 4210 = NGC 5004B is 5.3' NW. Member of AGC 1656.

600/800mm - 24" (5/20/17): at 375x; moderately bright, fairly small, slightly elongated N-S, ~40"x30", high surface brightness. Contains a relatively large very bright core and a thin halo that quickly fades out.

Brightest in a trio with NGC 5004A 3.5' S and IC 4210 5.3' NW. NGC 5004A appeared faint, small, elongated 2:1 N-S, 0.5'x0.25', low even surface brightness. A mag 12 star is off the southeast side [46" from center]. IC 4210 appeared very faint to faint, small, elongated ~4:3 N-S, ~24"x18", low surface brightness, very weak nucleus. A mag 15.2 star is 0.8' SSE.

Notes by Steve Gottlieb