Harold Corwin

IC 111, like IC 110 (which see), is probably lost. Bigourdan has three observations of I111 on two different nights at two different positions. His first micrometrically measured place, which is the IC position, comes from 5 November 1885, but there is nothing at all within an arcmin of that position. He describes the "object" simply: "This object could be a star accompanied by a little nebulosity."

The second position, from two measurements on 19 December 1900, is about 2 arcmin away from the first in the midst of an asterism of 6 faint stars. This is not the IC position, so even though Bigourdan's description ("Slightly granulated object about 30 arcsec in diameter; it could be formed by several small dispersed stars in the guise of a pretty nebulous ensemble") and position are appropriate for the asterism, I can't really take this as the IC object.

What, then, does his first observation 15 years earlier refer to? Unless he misidentified his comparison star (he calls it BD +33 250), this is one of Bigourdan's illusory objects like NGC 2529 and NGC 2531.

He also claimed to have found IC 110 nearby. That, too, is missing, and I don't see a pair of objects, stars or galaxies, in the area offset from a star similar to BD +33 250 that might fit his observations.

Like the two stars that are near the estimated position of IC 110, the six stars perhaps forming IC 111 are quite faint. The brightest of them is V = 15.2 which must have been close to the limit of Bigourdan's 30-cm refractor. There is another even fainter star to the southwest, as well as a faint, small galaxy in the midst of the asterism. Both are so faint, however, that I doubt either played any role in Bigourdan's observations.

― 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