Re: [LEAPSECS] What problems do leap seconds *really* create?

From: Steve Allen <>
Date: Thu, 30 Jan 2003 01:38:21 -0800

On Thu 2003-01-30T00:28:57 -0800, Ken Pizzini hath writ:
> Right, but in its way UT1 is "king" because that is the measure of
> earth-position time which is used in the definition of our current
> time standard, UTC.

I would go so far as to argue that UT1 is not time, but angle.
UT1 does not measure what we now understand to be time, it measures
the spin of a nonrigid body whose atmosphere, oceans, mantle, core,
sun, and moon are all doing strange things impede uniformity.
Unfortunately we have a history which very strongly confuses the
distinction, not the least being because we still communicate UT1 with
units that make it look like time. For technical communications it
might be a trend towards better thinking if the switch were made to
use a vocabulary which always gives UT1 in degrees.

> Some appear
> to feel that this history is important to preserve in our civil time
> standard ("UT1 rules!" "UTC ain't broke"); others appear to feel
> that it is irrelevant ("Just use TAI, dammit!").

Do not confuse things. I do not think that there is anyone on this
list, or anywhere, who would disagree with the current use and
definitions of UT1 and TAI. Only civil time and UTC are at issue.

Steve Allen          UCO/Lick Observatory       Santa Cruz, CA 95064      Voice: +1 831 459 3046
PGP: 1024/E46978C5   F6 78 D1 10 62 94 8F 2E    49 89 0E FE 26 B4 14 93
Received on Thu Jan 30 2003 - 01:38:36 PST

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