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    Re: Emergency Navigation
    From: Örjan Sandström
    Date: 2012 Jul 14, 05:43 -0700

    one could always use the poem for equation of time that I first saw in "The Lo-Tech Navigator by Tony Crowley, inspiration sprung from "Emergency Navigation" by David Burch according to author, uncertain on copyright so i wil not reproduce it here.
    it gives an interesting way to memorize the equation of time.
    To that poem I added (ok, ok, tried to) memorizing 7 points of the analemma across 8 dates.
    both solsitces Dec ±23.44°
    December 22 is -1m 20s
    June is +1m40s
    if both are taken as 1.5

    both equinoxes Dec 0° (again easy part)
    September one is -8m
    March is +7m20s

    crossing point april 13 <-> August 30 Dec N9° +35S
    add to that four points of the sides
    may 14 Dec N18.8° and -3m45s
    jul 26 Dec N19.5° +6m33s
    february 10 Dec S +14.5° +14m14s
    november 6th Dec S 16° -16m 27s

    If you remember these you could plot thm on some paper and join them by hand to end up with a reasonable analema giving values for declination and equation of time to surprizing precission, I usually get within 30' when using this not GPS but...

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