[time-nuts] On Setting the Astronomical Time

Dr Bruce Griffiths bruce.griffiths at xtra.co.nz
Sun Jun 10 17:14:54 EDT 2007

M. Warner Losh wrote:
> In message: <20070610173720.211CEBE20 at ip-64-139-1-69.sjc.megapath.net>
>             Hal Murray <hmurray at megapathdsl.net> writes:
> : 
> : > Is there some way to get TT to better than a tenth of a second, or is
> : > the earth just too sloppy of a time keeper? 
> : 
> : My guess...
> : 
> : The earth is sloppy on this scale.  If it wasn't, we could predict leap 
> : seconds.
> UT1 is a smoothed function, not an instantaneous one, since it factors
> out seasonal variation that's in UT2.  NIST doesn't publish DUT1 more
> accurately than milliseconds with a +/- 5ms caveat.  So +/- 100ms is
> "only" 20x worse than data published at nist.
> Warner
Try subscribing to the IERTS prediction service, which will email 
predictions of DUT1 at regular intervals.
Failing this just download their predictions.


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