NGC/IC Project Restoration Effort

===== NGC 4802 is most likely also NGC 4804. But that is not absolutely certain. Here is the story. N4802 is just where Tempel placed it in his observation of 20 April 1882. Herbert Howe, however, says "This was searched for in vain one night. Its description is so similar to that of 4804 that they may be identical, if the declination of 4802 is just 1 degree in error." Dreyer adds to this in an IC2 Note, "Tempel says it is 8 seconds following Lamont 1234 (10 mag), but this identification may be wrong." I have not yet been able to find the Lamont list, but Tempel's observation, as I said, is exactly right: the galaxy is just where he measured it to be, and his description is apt, so I have no reason to doubt his identification of the star. So, I wonder if Howe somehow confused N4802 with N4804 -- the latter galaxy is NOT in its nominal position. It was found by WH on 27 Mar 1786 in Sweep 548. His published list has it 30m 45s preceding and 18 arcmin south of 68 Virginis. Checking the Herschel Archives, however, shows that these offsets were calculated later from times and north polar distances recorded during the sweep. If WH's recorded north polar distance was 100 deg 56 min rather than 101 deg 56 min as in CH's copy of the sweeps, then the calculated offset would become 42 arcmin north of 68 Virginis, and the object is certainly the same one Tempel saw. However, WH's description reads, "Suspected a pB star, with a seeming brush to the np may be a small nebula close to it, but there was no time to verify it." Just about an arcminute north of WH's position is a double star whose orientation is northwest-southeast, and whose components have virtually identical magnitudes (13.85 in GSC; probably around 13.3 or 13.4 in V, depending on the stars' colors). It is just possible that WH saw the double star and in his hurry, mistook it for a star and a nebula. Also arguing for taking WH's 101 degrees at face value is the fact that none of the other nebulae that he found during the sweep have serious errors in their positions (these are NGC 4714, 4748, 4782/83, 4794, 4825, and 5094). I think it's more likely, though, that he simply made a 1-degree error in his north polar distance. This would, of course, explain Bigourdan's not finding the object at the NGC position; Dreyer mentioned this negative observation in his Notes in the Scientific Papers. So, in the end, the most likely explanation is that WH saw the same object that Tempel did nearly a century later. But given the double star, I've kept the colons, just in case.

===== NGC 4802 17.5" (3/23/85): fairly faint, very small, weak concentration to a virtually stellar nucleus. A mag 11 star is just off the SE edge. Located 30' NE of the NGC 4782/NGC 4783 pair.