Overlaid DSS image of NGC 1105, 30' x 30' with north at top and west to the right
IC 1840, MCG-03-08-004, NPM1G -15.0144, PGC 10333
|Size ||0.48' x 0.461' @ 45°|
|Right Ascension ||2h 43' 42.0" (2000)|
|Declination ||15° 42' 20" S|
|Description ||vF, vS, R|
NGC 1105 = IC 1840 = MCG-03-08-004. My previous decision to list two galaxies under the number "NGC 1105" was misguided. After reviewing the evidence, I've decided to go with historical precedent and let Leavenworth's sketch -- which clearly shows that NGC 1105 = IC 1840 -- provide the final word.
However, for those still interested, here is the full story.
The NGC galaxy was found in 1885 by Leavenworth with the 26-inch refractor at Leander McCormick Observatory. As with most of the faint nebulae discovered visually with this telescope, the discovery position is crude, especially in RA. Fortunately, Leavenworth has left us a sketch that shows conclusively that his object is identical to IC 1840. The four stars to the west of the galaxy -- looking like the top four stars in the cross of Cygnus -- are all shown in the sketch along with the galaxy.
The second candidate comes from Herbert Howe. Working with the 20-inch refractor at Chamberlain Observatory just outside of Denver, he could not find anything at the position given by Leavenworth. However, "... four minutes following was a very small nebula, about equal in brightness to a star of magnitude 13. As Leavenworth observed his nebula only once, and took its place roughly, the two may be identical." Dreyer took Howe's "may be identical" as "indeed are identical" and put Howe's RA in the IC2 Notes with only the qualification, "... (nothing in the place given by Leavenworth)."
So, we have two galaxies for one NGC number (where is Solomon when we need him?!). My previous solution added "e" and "w" suffixes to the NGC number for the two different galaxies. Not very satisfactory for the purist, I'm afraid, but it did give some credit to each of the observers, and attempted to deal with Dreyer's Note in IC2.
As I've said, however, my current sensibilities are offended by this Solomaic decision, so I've reverted to using historical precedent and ignoring Dreyer's Note. For what it's worth, the galaxy that Howe found is now called MCG-03-08-036.
9 objects found within 60'
Drawings, descriptions, and CCD photos are copyright Andrew Cooper unless otherwise noted, no usage without permission.
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