Harold Corwin

IC 4540 is lost, unless Wolfgang's guess that it is the double star a few arcmin north of SAO 120946 is correct. In this case, Swift's position is 45 seconds of time and 3 arcmin off, not unusually large for Swift's later positions. His description "B * in field n partly obscures it" has the star misplaced if Wolfgang is correct -- it is south of Wolfgang's double rather than north.

Nevertheless, the double is the only reasonable possibility that I see in the area, so I've kept it in the table. Interestingly, M 5 (NGC 5904) is about 20 arcmin northwest of the double. I wonder if Swift saw it while he was sweeping for new nebulae, and if he did, why he did not mention it in his note for IC 4540.

Finally, I should note that I checked every "bright" star in this POSS1 field and found no "vF, pS, mE" galaxy near any of them. My hesitation in accepting the double star as Swift's object is that it is close enough that he probably would have called it "vS" or "eS" rather than just "pS". Well, I've put it in the table, anyway, like it or not: it is certainly a candidate and Swift has been further off in describing many other of his "novae".

― IC Notes by Harold Corwin

Drawings, descriptions, and CCD photos are copyright Andrew Cooper unless otherwise noted, no usage without permission.

A complete list of credits and sources can be found on the about page