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    Re: Lat/Lon by "Noon Sun" & The Noon Fix PROVE IT
    From: James N Wilson
    Date: 2009 Jun 7, 18:19 -0700
    Dave:
     
    Sorry to take so long to reply, but I've had to untangle myself several times from being wrapped around the axle. Translating what I do graphically into mathematics has proved elusive. My analytic geometry is rusty, but I think the problem is a wrong assumption somewhere.
     
    One of the benefits of the graphic approach is that the exact value of hs doesn't need to be matched. By taking several measurements, the needed value is bracketed. I've belatedly remembered that in conjuring up this method, I initially calculated two values of Dhs for two values of DWT, thus establishing the different slope of the adjusted hs vs WT line, and bracketing the selected value. I discarded that idea in the interest of simplification, although I think it would be needed for the moon. When I did a check on one of George's problems, a one minute change in DWT resulted in a three second difference in the time of meridian passage. So, I think that the simplification is justified.
     
    I still wish I could translate this into mathematics, because that would allow me to examine lots of cases. I'll keep trying.
     
    Sorry about the lapse. I recollect a joke about that: "As we get older, the first thing to go is our memory, and I forget what the second one is."
     
    Jim Wilson

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