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Re: How did Sumner navigate in 1837?


Subject: Re: How did Sumner navigate in 1837?
From: Noyce, Bill (william.noyce@XXX.XXX)
Date: Mon May 19 2003 - 08:34:50 EDT


Jim Thompson asks:

> To further demonstrate my ignorance, have I made the correct defintions for
> the variables?
> T = chronometer GMT
> D = declination (from almanac)
> L = latitude (from dead reckoning)
> H = altitude (from sextant)
>
> log (1-cos T) = log [cos(D-L) - sin H] + log sec L + log sec D

T here is the "Local Hour Angle" -- the angle at the pole between the
body's meridian and the observer's. I believe you've got the others
correct. Of course, H represents the sextant altitude *after corrections*.
        -- Bill





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