Andrew Cooper
Apr 14, 2007    Pu'u Kuainiho (map)
76mm f/6 APO

A rich region of clusters interlaced with faint but distinct nebulosity near θCMa, a north-south band of nebula over a degree long and less than ½° wide, framed by the clusters NGC2343 on the east, and NGC2335 on the north, as well as Cr465 and Cr466

Harold Corwin

The IC position, claimed to have been taken from Isaac Roberts's short note in AN 3509, is not from that note. Roberts's position is for BD -10 1848 and the HII region surrounding it, and that is the position that I've adopted in the table. Roberts copied it correctly from the BD into his note, but the IC position points to a bit of nondescript space about 20 arcmin southeast of the HII region.

There is an additional reference to this nebula in Wolf's note "Extended Nebulosities" in AN 4082, though Dreyer did not include that as a source for this object in the IC. Wolf notes that the nebula covers "many square degrees" and stretches at least from Roberts's nebula in the north on south to BD -12 1771.

Wolf's description of this large star-forming region is fairly good as far as it goes. The brightest, largest nebula is indeed Roberts's, but Wolf found the 2.5-degree long S-shaped nebula to its south and east. This actually extends a bit more faintly at least another 2 degrees east from its northern end, but Wolf apparently did not photograph that portion of it. NGC 2327, a small compact nebula, probably also an HII region or at least a part of one, is embedded in the sinuous nebula south of I2177.

I suspect that Dreyer was somewhat influenced by Wolf's description, so decided to give it some weight, but tried to retain Roberts's data as the main source for this object. This would account for the position southeast of the center of Roberts's object. So, I've simply gone back to his data for the main position for I2177. Given that Wolf's note is pretty accurate, though, I've also included the approximate center of gravity of his much larger S-shaped nebula under same number with a directional subscript.

― IC Notes by Harold Corwin

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