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    Graphical lunars
    From: Francis Upchurch
    Date: 2015 Feb 26, 23:24 -0800

    Thanks Robin,

    Looks like an interesting challenge. Stereographic plotting sheets sounds like the answer. as you say, do not need charts.

    Re the lunar clearance. I may  have got all this wrong, but page 87 John Karl (see attached, hope John doesn't mind?) gives a great diagram that suggests to my simple mind that you can draw out the moon/sun triangle on a globe and the great circle LD(sd) and then the fully corrected LD(o). So am I right in thinking that if you had a big/accurate globe, you could do this? If so, could you instead use a stereographic plotting chart and measure the LD(o) as a straight line on a flat plotting sheet?

    Maybe I have it all wrong. Perhaps John Karl could give his opinion on this as well?(thanks for the great book! I use the formulae to do lunar clearance with calculator and Fuller slide rule.)

    Look forward to receiving your advice, both.



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