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    Henning Umland's spreadsheets.
    From: Bill Lionheart
    Date: 2018 Apr 9, 02:20 +0000

    Next month I am sailing from St Lucia to Bermuda and then to NY on a
    friend's yacht (lucky me!) . I said I would  show the crew some simple
    celestial navigation, and it is a grat chance for me t practice
    sextant work myself with I hope clearer sky than I am used to!
    I currently use my own rather eccentric python scripts using the ephem
    library but I wanted to show them sight reduction on spreadsheet so I
    went back to Henning Umland's excellent spreadsheet
    "Sun and Moon Almanac  V1.51  for the Years 1975-2015"
    It seems the version I have has a hard coded limit on the year as it
    does not have this year's delta T, and I think the one on Henning's
    web site has not been updated. It is an easy matter to edit the
    javascript to update Delta T, but I may be reinventing the wheel here,
    perhaps someone has a version working for 2018 already?
    (we had an earlier discussion of a java script bug, due to a change in
    the trunc function in java script as I remember, but that was a few
    years ago).
    Best wishes
    Bill Lionheart

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