William Herschel discovered NGC 2232 = H VIII-25 on 16 Oct 1784 (sweep 296) and recorded "The 10 Monocerotis surrounded by many bright stars." His position matches the bright star. The position in the Lynga catalogue, RNGC, NGC 2000.0 and Sky Catalogue 2000 is about 20' too far west! Brian Skiff suggests a centroid position of 06 28 02 -04 50.8 based on the star GSC 4793-2505. See my RNGC Corrections #7.

By analyzing William Herschel's earlier "reviews" of bright stars (before his systematic sweeps), which resulted in the discovery of many double stars, Wolfgang Steinicke found that Herschel discovered the cluster on 5 Dec 1779 using his 6.2" reflector. This is apparently his earliest non-stellar discovery!

400/500mm - 17.5" (12/28/94): at 100x appears as a scattered group of bright stars surrounding 10 Monocerotis (V = 5.1) with the remaining stars forming a wedge tapering to the SW. Includes 7 brighter mag 8-10 stars and another two dozen fainter stars. Richest surrounding 10 Mon and five brighter stars form a distinctive box around the bright star. Too large and scattered for higher power.

Notes by Steve Gottlieb