Re: [LEAPSECS] the tail wags the dog

From: M. Warner Losh <imp_at_BSDIMP.COM>
Date: Mon, 23 Jan 2006 09:33:10 -0700 (MST)

In message: <20060123145139.GC4587_at_ucolick.org>
            Steve Allen <sla_at_UCOLICK.ORG> writes:
: The legal time of the US is (in many more words) GMT.
: The officials who are charged by congress with the task of providing
: time provide UTC.

The legal time in the US is the mean solar time at a given meridian,
as determined by the secretary of commerce (the actual law is a little
more verbose than this, but this is an accurate boil down) plus some
weird options for 'border states' which timezone they are in. This is
why NIST provides UTC and leap seconds happen on the UTC schedule
rather than some other schedule that would produce the same results.
It is also why there are leap seconds and not the old-style frequency
adjustments + tiny steps. Both of these schemes fit the law, as it is
rather vague in the words it uses in a legal sense (the term mean
solar time isn't legally defined, but does have an accepted scientific
meaning). Other schemes could also fit the law that aren't UTC today
since there's no what we would call 'DUT1 tolerance' written into the
law...

Warner
Received on Mon Jan 23 2006 - 08:34:19 PST

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