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    Re: Lunar distance calculations
    From: Ken Harris
    Date: 2022 Mar 12, 19:47 -0800

    Mmmm.  Which "Frank's Lunar Analyzer" are you using ?  What latitude are you using ?  I see you say "Abbreviated output for N39.0 W122.0", but my software defaults to N38.  If I use N39, it's within 0.2 arcminutes of "Frank's Lunar Analyzer" :

    python cel-nav-skyfield.py -t 2022-03-11T22:33:13 -g 39,-122,0 | grep -e semidiameter -e separation_from

    # semidiameter(apparent) : 0.0

    # semidiameter(apparent) : 14.9

    # apparent0.separation_from(apparent1) : 29deg 19' 21.9"

    # separation_from minus semi-diameters :  29deg 04' 27.5"

    What "height of eye" are you using ?

    I have skyfield version 1.42.  Numpy v. 1.21.5-1. Python 3.10. Fedora 35 !
    Strangely, if I use N38, I get a result that is 0.2 arcminutes different than yours (perhaps due to skyfield, numpy, python or OS differences) :
    python cel-nav-skyfield.py -t 2022-03-11T22:33:13 -g 38,-122,0 | grep semi-
    # separation_from minus semi-diameters :  29deg 05' 10.9"
    If I modify my program to display "Geocentric Lunar Distances", it agrees with https://clockwk.com/apps/predict exactly : https://pastebin.com/1uBaGpAe
       
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