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    Re: leap seconds a navigational hazard, says expert
    From: Brooke Clarke
    Date: 2003 Aug 9, 09:29 -0700

    There's another problem for me and that's Sundials.  There are many dials that are accurate to 15 seconds and changing to a new time format where the time no longer matches the Earth's rotation will make them obsolete.

    Have Fun,

    Brooke Clarke, N6GCE

    Paul Hirose wrote:
    Jared Sherman wrote:
    "But the article referenced claims a 13 second difference...which
    shouldn't matter if the system is correcting for it."
    That "if" is where the danger lies. The correction for the difference
    between time scales is done in software written by fallible humans.
    Remember the Mars mission that failed because of a misunderstanding
    about SI vs. US units?
    On the other hand, I can understand the astronomers objecting to a
    change in UTC. A lot of software must have been written with the
    assumption that UTC and UT1 would be within a second of each other.
    Letting the difference climb higher may break some programs.
    As far as I know, the Nautical Almanac still tabulates positions as a
    function of UT1. If not for leap seconds, we'd now be subtracting
    about 32 seconds to convert from UTC to almanac time. That's
    equivalent to 8 minutes of longitude.
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