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    Re: getting GHA from MICA
    From: Sean C
    Date: 2014 Mar 21, 14:30 -0700

    "My later program, Lunar3, is better for navigation. It's primarily for lunars, but will also compute altitude intercepts." -Paul

    Speaking of lunars, I've been using all of these programs and Frank's web page to check my work after manually (on a calculator) working some lunars. If I understand correctly, the "corner cosines" Frank writes about should be derived from the apparent altitude of the body at the time of observation. I'd like to ask everyone how best to find Ha from Hc. Currently, I'm using Hc & HP to estimate the parallax in altitude, then using trial and error to arrive at the correct value. I do the same for refraction, but this is generally easier since the value's rate of change seems to be slower. I tried thinking of a way of reversing the equations, but since the correction is derived from the value I'm seeking (and I'm no good at math), I can't figure it out. Any help would be greatly appreciated.

    Sean C.
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