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    Re: 0000 not 2400?
    From: John Simmonds
    Date: 2004 Oct 18, 23:36 +1000

    actually, in the military 24 hour clock .. midnight does not exist

    the time advances from 23:59:59 to 00:00:01

     

    John


    live every day like it may be your last .. cause one day it will be



    On Mon, 18 Oct 2004 08:01:38 -0300, Jim Thompson wrote:
    > I am revisting my understanding of how dates change around the
    > world over time (George called time/dates "slithery" -- no better
    > word for it!).
    >
    > I am learning that times and dates, an arbitrary measurement tool
    > applied to our spinning earth for human convenience, must have a
    > set of carefully defined, fixed, arbitrary conventions to work.
    > One example is using Time Zone Y on ships at sea, as agreed upon in
    > 1917 at the Anglo-French Conference on Time-keeping at Sea. But I
    > think it would be safe to say that another convention would be to
    > avoid using the term "2400".
    >
    > Although we can think and write the term "2400", it has no
    > practical meaning, is that right?  As soon as the time advances
    > past 23:59:59, then from a navigator's perspective the date changes
    > to the next day, at time 00:00:00.  The term "2400" seems to refer
    > to a non-entity, a purely abstract instant of time past 2359 when
    > it is midnight, but the date is still the same day.
    >
    > To resolve that conundrum, I revised the time-date conversion table
    > at
    http://jimthompson.net/boating/CelestialNav/TimeDateConversionTable.ht
    > m by changing the entries from 2400 to 0000, and shifting the date
    > relationships accordingly.  But the original version that used 2400
    > was based on the old US Coast Guard manual, which used 2400.  I do
    > not know the historical context of their use of "2400", but today I
    > think 0000 makes more sense.
    >
    > Am I merely catching up with the obvious?
    >
    > Jim Thompson
    > jim2{at}jimthompson.net
    > www.jimthompson.net
    > Outgoing mail scanned by Norton Antivirus
    > -----------------------------------------

       
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