John Herschel discovered NGC 7154 = h3900 on 23 Sep 1834 and recorded "B; pL; glbM; more nebulae hereabouts." The next sweep he logged "B; pL; irreg R; glbM; r; 60"."

Based on photographs taken at the Helwan observatory in 1919-20, it was described as "pF, 1' x 1/2', irr shape. Appears to be two small spirals very close together."

300/350mm - 13.1" (8/5/83): very faint, elongated 3:2, low even surface brightness, diffuse, requires averted.

600/800mm - 24" (9/25/19): at 375x; moderately bright, fairly large, slightly elongated, ~1.5' diameter, weak concentration, fairly low - though irregular - surface brightness. A very faint mag 15-15.5 star is superimposed on the south side. A mag 14.8 star is 1.6' NW of center.

First in a large group (LGG 450) that includes HCG 90 (NGC 7172-7176). MCG -6-48-4, located 12' NW, appeared fairly faint, slightly elongated E-W, 0.5'x0.4', even surface brightness. ESO 404-12, located 26' NE, appeared moderately bright, slightly elongated NW-SE, 1.2'x1.0', brighter core. A mag 14.6 star is superimposed on the east side.

Notes by Steve Gottlieb