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    Re: Interpolation to latitude
    From: Peter Hakel
    Date: 2009 Nov 12, 17:52 -0800
    The Rising and Setting Phenomena section of the Nautical Almanac states:

    "On the right-hand daily pages are given the times of sunrise and sunset, [...] twilights [...]"

    "These times, [...], are strictly the UT of the phenomena on the Greenwich meridian; [...]"

    "They are approximately the Local Mean Times (LMT) of the corresponding phenomena on other meridians; they can be formally interpolated if desired."

    "The tabulated times may be regarded, without serious error, as the LMT of the phenomena on any of the three days on the page and in any longitude.  Precise times may normally be obtained by interpolating the tabular values for latitude and to the correct day and longitude; [...]"

    Peter Hakel

    From: George Huxtable <george@hux.me.uk>
    To: navlist@fer3.com
    Sent: Thu, November 12, 2009 4:09:37 PM
    Subject: [NavList 10608] Re: Interpolation to latitude

    Joe Schultz wrote-

    "...2. The daily pages of a paper nautical almanac are very elegant.  Enter
    the daily pages with approximate time (left side) or position (right side),
    then extract position (left) or time (right) data.  Then apply some form of
    latitude and longitude corrections to get "exact" position or time.  And the
    daily pages operate in a zone time world, just like we do in our daily


    No. The Nautical Almanac works throughout in GMT, not in Zone Time.

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