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    Re Strange results from AM and PM sun shots, a solution found, should anyone be interested
    From: Alan S
    Date: 2012 Sep 29, 12:56 -0700

    Respecting AM & PM sun shots done on 24 & 26 Sept from the following DR position (GPS Fix), 34D 39.3M North x 77D 03.6M West, I had obtained strange results. Zn was for 24 Sept. AM shot, 91D. For PM shot, Zn was 269D, as I figured, having reduced the sights using USPS Sight Reduction Form SR 96a, Law of Cosines method. The above stated Zn's produced LOP's that were almost parallel, providing no calculated fix.

    I had posted a question regarding this anomaly, thinking that perhaps the very slight declanation on those dates might have caused the problem. Several people responded, offering thoughtful suggestions, Frank Reed included, who suggested a Naval Observatory Calculation format that I might use.

    When I recalculated the 24 Sept.Zn's, using the Navy format, I got the following results. Calculated fix just over 4 NM SW of GPS coordinates, that is 34D 35M North x 77D 04.5M West, certainly an improvement over what I had originally had, the final results are "reasonable", more than could be said for earlier results.

    I remain curious as to the nature of my original "blunder", having gone over my calculations a couple of times, without finding anything numerically amiss. That is, I suppose, grist for another mill, on another day.
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