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    Re: Finding The Symmedian
    From: Andrew Nikitin
    Date: 2010 Dec 23, 17:15 -0800

    > repeats the algorithm provided on the back pages of the Nautical Almanac

    I did not claim that the formula is new. I've even seen it several times on this very forum. However, I have a feeling that many people consider it too much of a dark magic to be comfortable with.
    I just tried to show that with the right mindset and if you know where to make a turn, the formula is "obvious" and can be produced on the spot without looking in the almanac (that is how I produced it for the purpose of writing that post). And the formula is simple enough to be programmed right away into a calculator. (I tested that assumption by actually programming it in my calculator. I testify that it was not difficult or time consuming.)

    > what is described in the Almanac is an iterative procedure

    I think the note regarding iterativity applies not just to a formula but to entire concept of Hilaire LOP. If AP is widely different from actual position, calculated azimuth may be noticeably different from "true" azimuth (the one that would have been observed if it was possible). As a result, LOP would be slightly off from "true" LOP. On a good side, the new position obtained this way is usually close enough to true position, so if it is used an new AP (and all azimuths and distances are recalculated for this new position), your are golden.

    The reason NA mentions that this is an iterative process only in association with the formula and not elsewhere, is that if you are going to use the formula, this means that you are using some kind of computer anyway, and recalculating new azimuths and Hc for all sights is trivial. So you should be diligent and just do it.
    On the other hand, if you are not using formula and using plotting techniques to find fix, this means that your are probably using tables and recalculating az and Hc would double your work. So you should be diligent and spend your valuable time doing something more productive.


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