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    Re: When did the Atumnal Equinox occure this year?
    From: Dave Walden
    Date: 2019 Sep 27, 12:26 -0700

    That's a lot of decimal places, but I don't belive delta T is 71.4 sec.  More like 69.184, not including the current  delta UT1 which is about -0.15 seconds.

    • since 00h 00m UTC 01 Jan 2017, the cumulative leap second count is:
      TAI-UTC = 37 seconds (exactly)
      and GPS Time-UTC = 18 seconds
    • users may compute Delta T using the relation:
           Delta T = 32.184 s + (TAI - UTC) - (UT1 - UTC)
      where
           (TAI - UTC) is the cumulative number of leap seconds
      and
           (UT1 - UTC) is a standard EOP product available below.

    ***************************

       COMBINED EARTH ORIENTATION PARAMETERS:                                   
                                                                                   
                                  IERS Rapid Service                               
                  MJD      x    error     y    error   UT1-UTC   error             
                           "      "       "      "        s        s               
       19  9 20  58746 0.20486 .00009 0.32295 .00009 -0.152909 0.000014          
       19  9 21  58747 0.20380 .00009 0.32167 .00009 -0.152551 0.000013          
       19  9 22  58748 0.20296 .00009 0.32040 .00009 -0.152107 0.000013          
       19  9 23  58749 0.20228 .00009 0.31937 .00009 -0.151650 0.000012          
       19  9 24  58750 0.20166 .00009 0.31850 .00009 -0.151219 0.000009          
       19  9 25  58751 0.20101 .00009 0.31774 .00009 -0.150916 0.000008          
       19  9 26  58752 0.20025 .00009 0.31709 .00009 -0.150897 0.000008          
       
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