In message <20070117122430.GA23443_at_fysh.org>, Zefram writes:
>IERS Bulletin A gives an expression for the uncertainty of its UT1-UTC
>data predictions:
>
> S t = 0.00025 (MJD-today)**0.75
>
>where "today" is the MJD of the bulletin's publication. The Bulletin
>only predicts a year ahead. Applying that formula gives an uncertainty
>a year ahead of 21 ms.
The question is what domain of validity the above formula has ?
In the builletin they only apply it up to 40d.
For an argument of 10 years the result is 0.12 seconds.
For an argument of 100 years the result is 0.66 seconds.
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Received on Wed Jan 17 2007 - 04:59:46 PST