TAI zone?

Clive D.W. Feather clive at davros.org
Fri Jul 1 11:23:49 UTC 2011

Guy Harris said:
> What day is it right now? :-)
> From what I can find, TAI is defined as "seconds since the TAI epoch", which, if this page
> 	http://www.hko.gov.hk/gts/time/basicterms-TAI.htm
> is correct, is "1958 January 1 d 0 h 0 min 0 s"; if so, presumably that's "1958 January 1 d 0 h 0 min 0 s GMT".

Not quite. TAI is a clock, with hours, minutes, and seconds. It was
synchronised with GMT (UT1, actually) at the start of 1958.

> I suspect that means that the answer to "what day is it right now" could differ between the UTC and TAI zones near the insertion of a leap second.

It differs anyway. At present TAI moves to a new day 34 seconds before UTC

> Then again, it could differ between different locations on the earth....

TAI and UTC aren't time-zone dependent.

Clive D.W. Feather          | If you lie to the compiler,
Email: clive at davros.org     | it will get its revenge.
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