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    Re: Graphs of Lunar Distances.
    From: Frank Reed
    Date: 2010 Oct 24, 19:34 -0700

    Hewitt, you wrote:
    "Error in Lunar: 0.9'
    Approximate Error in Longitude 28.3'."

    When I have used a Davis sextant for lunars my results had a range of roughly
    +/-2.5'. Sometimes, of course, you can do better just by chance, but in general, inexpensive plastic sextants are not suited to accurate lunars. They're great sextants within that expected range. You can sail oceans with them, no problem, if a couple of minutes of arc is not a serious concern as in traditional small boat line of position navigation.

    And you wrote (to Douglas):
    "This is interesting to me on two counts. First my results are in line with yours, which is heartening. "

    Seven out of eleven of Douglas's Jupiter lunars were within +/-0.22 minutes of arc --so your results are not actually in line with his. He has concluded that his lunars are much worse than this apparently because there is some kind of bug in his calculator clearing method.


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