[tz] Unearthly time zone in the news

[Steve Allen]

On Wed 2024-04-03T13:41:16-0700 Paul Eggert via tz hath writ:
> The "U" in "UTC" is completely inflated of course. It's no more "Universal"
> than the World Series is a world-wide contest.

Universal Time derives from the 1884 International Meridian Conference
where the delegates agreed on a Universal Day.  In the late 19th
century the meaning of universal was everyone in the world, not more
than that.  Universal Time is the subdivision of the Universal Day
which was resolved to be a mean solar day.  (It could have been worse,
they could have adopted a different trendy word for everyone in the
world like "Catholic Time".  The IMC did discuss using Rome or
Jerusalem as the prime meridian.)

Simon Newcomb attended the IMC until US Department of State kicked him
out for comments on the practical issues of defining a prime meridian.
A decade later astronomers from countries producing almanacs for
navigation all agreed to use Newcomb's expressions for the motion of
the earth and sun.  The result was every nation agreeing to Universal
Time for almanacs.  Ironically, as soon as that agreement went into
effect the place over which the mean sun stands at 12:00 Universal
Time began an increasing deviation eastward from Greenwich.  Now the
value of UT1 continues to increase its difference from the value of
the mean solar time at Greenwich Observatory, but this becomes
irrelevant as UTC without leap seconds will abandon close connection
with the sun and deviate 365.25 times faster from Greenwich.

--
Steve Allen                    <sla at ucolick.org>              WGS-84 (GPS)
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