Bindon or George Stoney discovered NGC 595 on 27 Dec 1850 with Lord Rosse's 72" (or perhaps on the 13 Sep 1850 observation, "full of knots") and an offset measured from a star superimposed on M33. The nebula was labeled as "1" on the diagram in the 1861 publication. No coordinates were ever measured at Birr Castle.

Heinrich d'Arrest independently discovered this HII knot on 1 Oct 1864 with the 11-inch refractor at Copenhagen and measured a fairly accurate position (4 seconds of RA too large). d'Arrest is credited with the discovery in the NGC. Truman Safford rediscovered it on 1 Nov 1866 with the 18.5" refractor at the Dearborn Observatory and recorded Sf 63 as "pF, vS, probably a well-known outlier of M33."

300/350mm - 13.1" (8/15/82): visible faintly with averted. Situated at the edge of a spiral arm.

400/500mm - 17.5" (7/5/86): very faint nebulosity in M33, located 4' NW of the center. Situated just off the west edge of the beginning of the spiral arm that extends north and then northeast from the core on the west side. This is a combination star cluster and HII region.

Notes by Steve Gottlieb