On Sun 2006-12-17T18:48:16 +0000, Poul-Henning Kamp hath writ:
> But you could conceiveably argue the point, that ITU-R only controls
> time, as far as it pertains to telecommunication and radio transmission
> of time signals, and that each country is free to use another
> timescale for civilian time.
>
> Unfortunately, the Metre-Convention and the Longitude Conference
> has nailed your left and right feet to the floor [1], so in practice
> ITU-R gets to decide all time.
If only it were evidently that simple. ITU-R TF.460 says the IERS
announces leap seconds, and the head of the bureau who makes such
decisions has indicated a desire to continue to do so, and the IERS
http://www.iers.org/MainDisp.csl?pid=36-25787&prodid=16
says "UTC is defined by the CCIR Recommendation 460-4 (1986)"
which the ITU-R has already superseded twice with no indication
that the IERS intends to heed any updated version.
The BIPM says
http://www1.bipm.org/jsp/en/ViewCGPMResolution.jsp?CGPM=15&RES=5
that UTC gives an indication of mean solar time, which it can only do
using leap seconds. The Metre Convention authorizes the BIPM as one
of the three agencies who have a say in these matters.
I don't see those feet nailed down. I see a gauzy web of
insubstantial constraints being held self-consistent only by the fact
that there once was consensus about how everything worked and there is
not yet consensus to overturn that.
To mix metaphors (and risk adopting Rob's tone), too many cooks spoil
the broth, possibly by pissing into it. In this case the cook who is
recognized as the holder of UTC does have his feet nailed down by the
ITU rules which say their documents must be sold, not given away. All
the other agencies contributing to this broth are allowed to work
openly and publish freely.
--
Steve Allen <sla_at_ucolick.org> WGS-84 (GPS)
UCO/Lick Observatory Natural Sciences II, Room 165 Lat +36.99858
University of California Voice: +1 831 459 3046 Lng -122.06014
Santa Cruz, CA 95064 http://www.ucolick.org/~sla/ Hgt +250 m
Received on Sun Dec 17 2006 - 20:57:29 PST