[LEAPSECS] nails in the coffin of mean solar time

[Rob Seaman]

On Jun 16, 2007, at 3:46 PM, M. Warner Losh wrote:


> A simple work around is to move time zones over one every few hundred

> years.  That's a lot easier than getting leap seconds right as most

> places do DSL.  A single year without a DSL transition would suffice.

> And each nation could choose the year they do it too, as there's

> really no need to coordinate.


There IS a need to coordinate - but even a coordinated dance of the  
timezones won't work, as three out of four Norwegian Fjord Ponies  
will tell you:

	http://www.youtube.com/watch?v=T3t86i1Y_so

UTC is both a flavor of universal time - that is, an approximation to  
GMT - as well as an report format for TAI.  Even during a leap  
second, UTC preserves a single, monotonic record of events worldwide.

Per-timezone daylight saving adjustments are possible precisely  
because the underlying unity of timekeeping is preserved elsewhere.   
What you describe would be a return to pre-universal time chaos.

Rob Seaman
NOAO