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    Re: 18 june 2013 lunar distance
    From: Antoine Couëtte
    Date: 2013 Jul 3, 08:48 -0700

    RE# 1 : http://fer3.com/arc/m2.aspx/18-june-2013-lunar-distance-Hirose-jul-2013-g24555

    RE# 2 : http://fer3.com/arc/m2.aspx/18-june-2013-lunar-distance-Hirose-jun-2013-g24541

    Hello Paul,

    I have to confess that I am bit lost:

    In RE# 2, I can read that you published the Moon and Altair coordinates as follows :


    USNO MICA 2.0
    106 34 28.48 (= 106 34.4747), calculated from geocentric apparent places with respect to true equator and equinox at TT = 03:31:07.1.

    12 49 1.478 -8 12 48.78 Moon
    19 51 28.291 +8 54 23.41 Altair

    Delta T = 32.184 + 35 - 0.0661627, the last figure from the USNO Earth
    Orientation database search page



    In RE# 1, for (apparently) exactly the same date and time "[2013-06-18 0330 UT1, 67.1178 delta T, DE406 ephemeris, Hipparcos second reduction]" I can read that you published the Moon and Altair coordinates as follows :


    From Lunar3 I get Moon coordinates

    -2.44969548e-003 -5.24187596e-004 -3.58294080e-004 au, or
    192° 04′ 40.973″ -08° 08′ 21.886″

    and Altair coordinates
    4.59325899e-001 -8.74784757e-001 1.54179599e-001 au, or
    297° 42′ 09.913″ +08° 52′ 09.188″


    I can see that both sets of results are quite different.

    For your information, I am computing:

    For the MOON:

    12h49m01.422s (192°15'21.323") and -8°12'50.265" , which differs by 1.7" from MICA (and stays well whithin my limitation of +/- 4")


    For ALTAIR:

    19h51m28.289s (297°52'04.334") and +8°54'23.397" , which which differs by 0.03" from MICA,


    As a conclusion, I would think that your earlier published results are the most accurate ones.

    Please be so kind as to bring me some light here.

    With many thanks in advance,

    As an ever untamed delta-T publishing fan, I am remaining,

    Most computationally yours,


    Antoine M. Couëtte
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