NGC/IC Project Restoration Effort

===== NGC 4426 = NGC 4427 is a double star. This is one of the very few objects which shows a bit of haste on Dreyer's part in his final work on assembling the NGC. D'Arrest's and Bigourdan's positions and descriptions are clearly pointing at the same object, and the two objects are adjacent in the NGC, yet not until he saw the proofs did Dreyer add the note "These are evidently identical (note added in press)." In IC2, he has an additional note: "According to M. Wolf (list IV.) only two stars 36 arcsec apart, n and s." The stars are actually separated by only 13-14 arcsec, and Wolf's southern position points to empty sky -- this may be a defect on his plate. In any event, there is no doubting the identification as both d'A and Bigourdan have two observations of the double, and both describe it as a small cluster, perhaps with nebulosity involved (there is none). There is a mistake in Bigourdan's notes, though his published position (in his first Comptes Rendus list) is correct. He chose an anonymous comparison star for NGC 4426, noting that it is "+1m 31s, -7 arcmin" from BD +28 deg 2116. The correct distance in RA is -29.8s, so Bigourdan may have meant to write -31s. Note, too, that Bigourdan came back to this after the NGC was published to measure NGC 4426 on 17 April 1888. His earlier position for NGC 4427 is from one estimate on 22 April 1886 with respect to NGC 4408 (which is 52s west and 2 arcmin north according to Bigourdan). The descriptions for both observations are virtually identical.