[ntp:questions] National time standard differences

Richard B. Gilbert rgilbert88 at comcast.net
Tue Feb 9 18:28:41 UTC 2010

David J Taylor wrote:
>>> I remember the flying of caesium or other atomic clocks round the 
>>> world, and that folks had to invoke relativistic corrections.  Were 
>>> these better than microseconds as well?
>> Please excuse me if I leave relativistic corrections to the late 
>> Professor Einstein!  It's not something I've ever needed to know!
> Richard,
> I meant the flying clocks (microseconds).  Relativistic corrections are, 
> I understand, needed for GPS satellites, though.

They are, indeed!  They are small, very small, but utterly necessary if 
you're counting your nanoseconds.

I'll settle for getting the seconds right.  Nothing I do requires 
nanosecond accuracy.

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