William Herschel discovered NGC 5480 = H II-692, along with NGC 5481, on 15 May 1787 (sweep 736) and described both as "Two, both F, R. The preceding pS, vgbM. The following vS, stellar, suddenly mbM. The place taken between them; in the parallel nearly, about 2 1/2' distance; the following about 1/2' more south." CH's reduction is much closer to NGC 5481. Bigourdan measured an accurate RA on 12 Jun 1887 (repeated in the IC 2 notes). The UGC declination is 20' too far south.

300/350mm - 13.1" (3/24/84): fairly faint, moderately large, almost round, diffuse, almost even or even surface brightness. Forms a pair with NGC 5481 3.2' E over the Bootes border.

400/500mm - 18" (4/26/08): fairly bright, moderately large, elongated 3:2 SSW-NNE, 1.2'x0.8', broad concentration with a brighter 25" core and a faint stellar nucleus using direct vision. Forms a very nice pair with NGC 5480 3.2' E.

Notes by Steve Gottlieb