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