[LEAPSECS] Leap Sec vs Y2K

[Steve Allen]

On Sun 2010-12-12T20:48:48 -0700, Warner Losh hath writ:
[regarding a 10 year advance predicion of leaps]

> It does seem like a reasonable compromise between different needs.  It

> would preserve the low-precision users (like PHP) to be more or less as

> accurate as they are today without modification, while not affecting the

> high precision users over much since they need DUT1 today anyway


I agree.

I suppose that the php API in the orgin of this thread is expected to
be used on web pages related to Jewish, Muslim, Adventist needs to
schedule events with respect to sunset.  I can say with experience
http://www.ucolick.org/~sla/sunset/
that meteorology can cause the predictions of sunset and sunrise times
to be off by minutes.  So a multi-year window of leap second
prediction will not notably degrade the current accuracy of this php
API.

The bigger picture is whether the ITU-R will redefine the civil notion
of the word "day" to be based solely on cesium atoms, and unrelated to
the passage of the sun across the sky.

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