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    Re: Lunar distance method of Chauvenet
    From: Paul Hirose
    Date: 2020 May 26, 12:07 -0700

    On 2020-05-26 8:00, Roger W. Sinnott wrote:
    > But I'm curious why you are
    > setting delta-T (or, ET - UT) equal to +10 seconds.  According to the
    > 2020 Astronomical Almanac, delta-T was +7.6s at 1855.0 and +7.7s at 1856.0.
    
    I'm not surprised there's a discrepancy. My delta T model is based on
    the paper by Morrison, Stephenson, and Hohenkerk, "Measurement of the
    Earth's rotation: 720 BC to AD 2015."
    
    http://fer3.com/arc/m2.aspx/Delta-T-long-term-formula-Hirose-feb-2018-g41332
    
    According to the table at the UK HO site, +10 s is about right. For
    convenience I rounded the value from my model to the nearest integer.
    
    http://astro.ukho.gov.uk/nao/lvm/
    

       
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