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    Re: Lunar distance accuracy
    From: Peter Fogg
    Date: 2007 Nov 6, 04:37 +1100
    The lunar was taken in the very rolly anchorage behind the reef. Not
    open ocean, but definitely a lot of motion. The moon happened to be
    nearing its highest point, providing several challenges. It was very
    difficult to get the sun over to the moon, and the high altitude made
    for a very awkward posture when I did. This sight was a prolonged
    struggle; I tried several postures but found nothing comfortable.
    All in all, I am pleased with how well it came out given
    the difficulties.

    With such good information as to author and date it took less than 30 seconds to find this at:

    It took longer to read the message. Nothing about sails (well, Arthur was at anchor at the time) and this seems to have been the conclusion:
    I felt I got a good look at a couple
    of the contacts but struggled with the others. The graph of the
    observations is more consistent than I would have guessed although I ended
    up pretty far off. I would guess that had I worked the longitude as I did
    with the first set, I'd be off by over 80 miles. Practice, practice,
    practice... I suppose I'll just have to spend more time in the

    On 11/6/07, Fred Hebard <Fred@acf.org> wrote:

    Arthur Pearson posted to this list in January or Febrary, 2003, the
    results of some sea observations of lunars compared to GPS or
    chronometer/radio time.  His conclusion was that they were accurate
    to about 30' of longitude, if I recall correctly.  The observations
    were made from a small yacht, which would be a more difficult
    platform for observation than a ship.  The sails and rigging did get
    in the way, if I recall correctly.


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