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    Re: Navigation without Leap Seconds
    From: Lu Abel
    Date: 2008 Apr 18, 09:10 -0700

    Geoffrey Kolbe wrote:
    > Well, my Long Term Almanac is nominally good up to the year 2050 and will
    > actually work OK up until 2060. So this is a very real question for me.
    >
    > I am assuming that if leap seconds are abolished, anyone using my tables -
    > which assume GMT, or UT1 as it is called these days - will know the
    > difference between broadcast time and GMT and use this as a correction to
    > broadcast time.
    >
    On the contrary, your long term almanac is based on the measurement of
    "what time is it" at some point in time (likely when it was published).
    So it does NOT correct for leap-seconds, since there is no way to
    predict when they will be inserted into UTC.   So it is effectively
    already practicing leap-second-less navigation.
    
    I don't know how old your long term almanac is, but if it's old enough
    it would be interesting to compare its data with current Nautical
    Almanac data; I'll bet there might be some small discrepancies in some
    GHA predictions.
    
    Lu
    
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