R.J. Mitchell and George Johnstone Stoney, LdR's assistants, discovered NGC 5721 and 5723 on 16 Apr 1855 during an observation of the NGC 5714 group. A diagram is accurate enough to clearly establish the identifications of NGC 5721 = MCG +08-27-013, NGC 5722 = MCG +08-27-014, NGC 5723 = MCG +08-27-015 and 5724 = mag 17 star.

RNGC misidentifies NGC 5721 as NGC 5722. The CGCG misidentifies the close pair as NGC 5721 + NGC 5723, instead of NGC 5721 + NGC 5722. Finally the MCG misplaces MCG +08-27-013 (the furthest west of the quartet) 2' south of NGC 5722, instead of 30" north. This error is carried forward into PGC.

400/500mm - 17.5" (6/27/98): this close companion to NGC 5722 required averted vision and concentration to momentarily glimpse a virtually stellar object <10" diameter, just 35" NNW of NGC 5722. This borderline detection was repeated several times knowing precise location.

Notes by Steve Gottlieb