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    Re: Advancing a position circle. was : [NAV-L] Positionfromcrossing two circles
    From: Andrés Ruiz
    Date: 2015 Feb 23, 12:47 +0100
    Dear Robin, 
    Well done!

    This remind me our private conversation about this issue in 2011:

    ...
    • The correction V*(t-tfix)*COS(Z-R) for Ho is only an approximation. See: Running fix- Papers.zip, I have implemented this methods.
    An exact solution says that the transferred CoP is deformed:
    • the radius ZD is the same in the original CoP and in the transferred one.
    • But its center (Dec, GHA) depends on your position. If You plot the circle, you obtain different centers choosing different points of the circle(lat,lon).
    • Thus, only one of the solutions for a double altitudes problem is OK, mathematically.
    See:
    ...

    Also I discussed about this with GH and H. Zevering in 2010. The problem was that without a plot like the ones you provide us, is very difficult to illustrate this fact.

    Thanks and best regards!

    --
    Andrés Ruiz
    Navigational Algorithms
    http://sites.google.com/site/navigationalalgorithms/
       
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