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From: Bill (no email)
Date: Sun Apr 17 2005 - 20:04:07 EDT
Fred wrote:
> Refraction is critical to clearing both interstellar and lunar
> distances. The mistake Bauer made in the table in his book is that he
> did not account for refraction. That, of course, would not be possible
> without knowing one's position.
I have a second edition paperback of Bauer's "The Sextant Handbook," circa
1995. Appendix F deals with interstellar angles. It would appear the first
three paragraphs have been revised, as the type is darker than the later
paragraphs. This is noticeable throughout the book when a few lines have
been changed.
In the revised paragraphs he does mention that refraction must be accounted
for, bur his method is simplistic. Take the difference between the two
object's refraction and subtract from calculated true separation. While it
works for stars at the same azimuth, it falls apart in other situations. A
few tenths of a minute off is not, IMHO, acceptable for establishing error
along the arc or lunars, where 0.2' off becomes 6' in latitude.
Bill
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