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Re: Rocky Mountain Lunar Distance


Subject: Re: Rocky Mountain Lunar Distance
From: Noyce, Bill (william.noyce@XXX.XXX)
Date: Wed Dec 18 2002 - 11:16:28 EST


George Huxtable says:

> And
> just making an ordinary linear interpolation for times within this 12-hour
> interval gives rise to a worst-case interpolation error of around 4
> arc-minutes in the Moon's declination. That is sufficiently accurate that a
> calculated altitude based on that dec. will not affect the accuracy of
> clearing the lunar distance.

But hadn't you better use a better declination when actually figuring
the "computed distance" to which you then compare your cleared distance?
Not a problem for navigators in Maskelyne's day, when these computed
distances were tabulated at 3-hour intervals...

        -- Bill





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