James Dunlop discovered NGC 7590 = D 477.1 = h3980 on 14 Jul 1826, along with NGC 7599 and recorded "two very small round nebulae [NGC 7590 and 7599], nearly the same RA, and differing about 1' in polar distances." John Herschel observed the pair of 2 Sep 1836 and logged "pB; pmE; gbM; 90 arcseconds, the preceding of two [with NGC 7599]."

300/350mm - 13.1" (11/5/83): faint, small, elongated SW-NE. A star is at the NE edge. Forms a pair with NGC 7599 4.9' ESE. Second of three with NGC 7582 9.8' SW.

600/800mm - 30" (10/21/17 - OzSky): at 264x; very bright prominent ellipse, very elongated 3:1 SSW-NNE,, ~2.1'x0.7'. Strongly concentrated with a very bright, elongated core that appeared mottled. A mag 12.0 is attached on the east side of the northern end of the galaxy. NGC 7590 is the second of three in the Grus Triplet with NGC 7599 5' ESE and NGC 7582 10' SW.

Notes by Steve Gottlieb