[time-nuts] The future of UTC
michael.cook at sfr.fr
Fri Jul 15 08:30:00 UTC 2011
Le 15/07/2011 07:57, Poul-Henning Kamp a écrit :
> Everybody but the time-lords have always been told to stay away from
> TAI in the strongest possible terms by said time-lords, who again and
> told the world to use UTC.
The time lords are not completely deaf. For more than 10 years there has
been debate about whether or not to revert to a TAI scale, but consensus
has never been obtained. There are three requirements for time
transmission that the current system supports in recommendation ITU-R
TF.460-6 which the americans are trying to vote out.
1. SI second ticks
2. corrections to UTC for earth rotation , DUT1, so that UT1 can be
3. A civil time scale, UTC which is a descendant of GMT and roughly
measures the mean solar day. One or other , if not both, figure in all
the legal codes of the planet.
The definition of 3 ensures that there are 86400 +/-1 ticks per
mean solar day . This is quite useful as my watch and just about
everyone else's measures days in 86400 units .
The proposed change to ITU-R TF.460-6 provides 1 but removes 2 and 3.
Sheer folly to my mind.
The current recommendation is good for another 2-300 years .
So in my humble opinion, the proposition for change should be rejected
until consensus be achieved and that ALL three above requirements are met.
More information about the time-nuts