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    Re: stange results from AM and PM sun shots
    From: Gary LaPook
    Date: 2012 Sep 27, 11:18 -0700
    You didn't state the times of your observations, if they were taken at about sunrise and sunset then the azimuths of the sun should be almost straight east and west. This is due to the declination being close to zero. On the dates of the equinoxes the sun rises on an azimuth of 090 and sets on an azimuth of 270 as observed from everyplace on earth. At low latitudes, say within the tropics, the azimuths at rising and setting are very close to  90 (or 270) plus or minus the declination.


    --- On Thu, 9/27/12, Brad Morris <bradley.r.morris@gmail.com> wrote:

    From: Brad Morris <bradley.r.morris@gmail.com>
    Subject: [NavList] Re: stange results from AM and PM sun shots
    To: NavList@fer3.com
    Date: Thursday, September 27, 2012, 10:08 AM


    Alan - Try taking your sights about 6 hours apart, as 6 hours * 15 degrees per hour is 90 degrees of separation between azimuths.

    Best Regards

    On Sep 27, 2012 1:05 PM, "David Fleming" <d.l.fleming.1@gmail.com> wrote:


    Your situation has nothing to do with Delination of sun being close to equator.

    The problem is the azimuths are nearly reciprocals of each other. Essentially a morning and evening sight on reciprocal azimuths are equivalent to two sights taken at approximately the same time. We can average them for improved accuracy but we can not produce a fix because they are not really that independent of each other.

    Dave F.
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