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    Appeal to forum members to collect data
    From: Jim Hickey
    Date: 2007 Oct 25, 10:52 -0700

    I would like to collect some data from a variety of observers using a
    variety of marine sextants taken in a uniform manner.
    What I am proposing is to collect data using the following method:
    1. Take 5 observations (moon and sun, star or planet) standing on
    land. No graphing, just 5 raw observations.
    2. Record name of observer, sextant used, power of sextant scope, GMT,
    date, Lat and Long, name of body used, distance (corrected with IE),
    barometric pressure, temperature, error in each observation (in
    3. I would propose using Frank's online calculator to evaluate the
    error in each observation using the known lat and long and letting it
    calculate the heights of the moon and body observed.
    4. Angular measurements reported in whole degrees and minutes rounded
    to the nearest 0.1'.
    5. Make the observations in good conditions and with the moon and body
    15 degrees or more above the horizon.
    6. Submit the results to me and I will accumulate the data in tabular
    form. I could provide an Excel template to use or the results could be
    sent in a set text format.
    My ambition in doing this would be to have some clear cut answers to
    the accuracy and precision questions that come up. What I have found
    is that although there have been many postings on the topic, there is
    always some question as to how the observation(s) were taken, the
    method of evaluation used or what almanac data was used.
    Once in electronic format we could proceed to analyze the data in a
    multitude of ways.
    I would invite comments on this proposal at this point and will remain
    hopeful that a few people out there would like to join the endeavour.
    To post to this group, send email to NavList@fer3.com
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