Harold Corwin

IC 397. I had this to say about IC 397 years ago:

Observed twice by Spitaler, but there is only an eF * near his position that he could not have seen. Another case of a misidentified comparison star, perhaps?</blockqoute>

This makes no sense to me now (Sept 2013) as Spitaler's position is about 20 arcsec north of a line of 4 stars, the northern-most a double. His measurements may refer to this asterism with an error of about 0.7 seconds of time and 20+- arcseconds in his observations or reductions.

Alternatively, there is another somewhat brighter and larger asterism just 20 seconds of time preceding and 3 arcsec north of Spitaler's position. This, too, is a possibility with a measurement or reduction error.

I also checked that reversing the signs on Spitaler's offsets yeilded no nebulae or asterisms that he might have seen.

So which error do you like the most? I've included positions for all these stars -- and the two mean positions -- in the big position table. At the moment, I'm not inclined to choose between these two possibilities. And there may well be others that I've not considered yet.

Whatever happened, there is nothing obvious in the field, or in Spitaler's published measurements, that could lead us to the object he saw.

― IC Notes by Harold Corwin

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