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Re: Lunars: altitude accuracy

From: George Huxtable (no email)
Date: Wed Nov 03 2004 - 10:46:52 EST

  • Next message: Herbert Prinz: "Re: Averaging"

    Frank Reed proposed that-

    >>I general, good (slightly approximate) expressions for the required accuracy
    >>of the altitudes are:
    >>AccuracyBody = 6' * sin(Distance) / cos(BodyAltitude)
    >>AccuracyMoon = 6' * tan(Distance) / cos(MoonAltitude).
    >>
    >>I have never seen these expressions in print anywhere. Has anyone else
    >>encountered them?

    and I replied, in 1 Nov,

    >"No, and they don't 'feel' correct to me."

    To which Frank responded-
    >
    >You need to do some real examples before you worry about how it feels...

    Since then, I have done just that, and done a bit of pondering about the
    matter. I am now fully convinced that Frank's analysis was correct, and my
    own understanding was quite wrong.

    So I'm grateful to Frank for making me think rather more deeply about the
    matter, and steering me on the right track, though some aspects continue to
    puzzle me.

    George.

    ================================================================
    contact George Huxtable by email at , by phone at
    01865 820222 (from outside UK, +44 1865 820222), or by mail at 1 Sandy
    Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK.
    ================================================================


  • Next message: Herbert Prinz: "Re: Averaging"



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