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    Re: Latitude by Talcott-Horrebow Method
    From: Peter Monta
    Date: 2018 Nov 6, 13:17 -0800

    However, nowadays the polar motion is predicted and published a year in
    advance in IERS Bulletin A to .001″ precision. Bulletin B has more
    accurate values determined after the fact.

    The uncertainty of the pole a year in advance is quite a bit larger than 1 mas, though.  Bulletin A says the uncertainty is already 13 mas for 40 days out, and gives a little power-law formula that gives 75 mas for a year out.  But yes, the measured values are good to 90 uas (~3 mm).


    Cheers,
    Peter

       
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