Complement to VII/239A

NGC 412

. Leavenworth has left us a sketch of this nebula, as well as the usual poor position and brief description. Unfortunately, his sketch shows only one star in the field, about 5 arcmin southwest of the nebula, so the field will not be easy to recognize. The sketch is one of the few to have the orientation marked, so that is not a problem here as it is with some of the LM nebulae.

In fact, I can't find Leavenworth's object anywhere near his position. Nor are there any other nebula/star pairs within several degrees of that position that match the sketch, either. The galaxy chosen by ESO, 3.8 minutes preceding and 19 arcmin south of Leavenworth's position does not match the sketch, so that cannot be the object, either.

Leavenworth added a note "Neb?" to his description, so it is possible that the object is simply a star. However, I could not even find two stars in the correct relative orientation in the area that would match the sketch.

The sketch is dated 15 Oct 1885. Leavenworth made at least four other sketches that same night. They are of N377, N540, N635, and N842 (all of which see). Of these, N540's identification is unsure, and N635 is three degrees south of its nominal position. Assuming all four identities, though, the average offset of Leavenworth's positions in RA is +25.3 seconds of time with a mean error of +-32.2 seconds, and a standard deviation in one observation of +-64.5 seconds (all are at roughly the same declination, so the conversion to arcseconds can be ignored given the size of these numbers). In Dec, the equivalent numbers are -5.3 arcmin, +-4.2 arcmin, and +-8.4 arcmin. Given offsets and errors of this size, and the three-degree accidental error for N635, NGC 412 could be ANYwhere within several degrees of Leavenworth's nominal position.

But I still can't find it. So, unless other folks want to spend more time on the field, NGC 412 is probably irretrieveably lost.



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