John Herschel discovered NGC 5545 on 27 Apr 1827 as he noted "a double nebula [with NGC 5544] which run together pos 10° nf by diagram." The Stoney brothers, LdR's assistants, found the pair on 10 Apr 1852 and noted "either a double nebula or 2 knots of one neb." R.J. Mitchell also logged NGC 5545 on 17 Mar 1855 while observing NGC 5544. He recorded a "D Neb; the p one NGC 5544] has a nucleus or a stellar point in the center, the following one [NGC 5545] is elongated, no nucleus but lbM." A sketch was made and included in the 1880 publication on plate V. John Herschel credited LdR with the discovery in the GC and Dreyer followed this in the NGC. Steinicke concurs that JH should be credited with the discovery.

The NGC positions for both objects are very close, but misleading as the declination for NGC 5545 (nearest arcminute) is slightly south of NGC 5544, instead of north.

400/500mm - 17.5" (3/23/85): double system elongated WSW-ENE and attached to NGC 5544 at the WSW end, 0.6' between centers. Appears larger than NGC 5544. The two systems are separated by just a small darker region of lower surface brightness but are not cleanly resolved.

900/1200mm - 48" (5/12/18): at 488x; the eastern member of this striking overlapping pair appeared fairly bright, very elongated WSW-ENE, ~1'x0.3'. Contains a brighter elongated core region (not as prominent as the core of NGC 5544). The northeast end (an outer spiral arm) dimmed significantly and appeared as a very low surface brightness curving arc. The western outer arm merged with the outer halo of NGC 5544 in a somewhat dimmer region.

Notes by Steve Gottlieb