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Re: F-ckin Leap Seconds, how do they work?


From: Marshall Eubanks <marshall.eubanks () gmail com>
Date: Thu, 5 Jul 2012 11:14:59 -0400

On Thu, Jul 5, 2012 at 9:55 AM, Peter Lothberg <roll () stupi se> wrote:
Leap seconds are to align the artificial and very stable atomic timescale
with the irregular and slowing rotation of the earth.

You are assuming facts not in evidence.  The rotation is merely irregular w=
ithin the capabilities of our scheme of measurement, calculation, and obser=
vation.  Once upon a time eclipses of the sun and moon were "random magic",=
 before the mechanism was understood.  So to the periodic cycles of the rot=
ation of the earth about its axis, the planet about the sun, etc., are view=
ed as "magical".  This is not due to magic, but rather limitations of under=
standing.

Earth is 10e-8 in frequency, a nanosecond a day is kindof 10e-14 on
frequency.


Tom has done the work to document it..

http://www.leapsecond.com/museum/earth/


And, by the way, the deformations and exchanges of angular momentum
that drive Earth rotation variations are probably the best understood
global geophysical processes there are.  Absolutely no magic is
required.

Regards
Marshall

--Peter



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