[LEAPSECS] the big artillery

Tony Finch dot at dotat.at
Wed Nov 5 06:11:38 EST 2014


Gerard Ashton <ashtongj at comcast.net> wrote:

> For example, the Standards of Fundamental Astronomy subroutine iauDat
> provides the delta between TAI and UTC, and the source code comments say
> "UTC began at 1960 January 1.0 (JD 2436934.5) and it is improper to call
> the function with an earlier date." In as much as UTC attempted to track
> UT2 in the 1960s, I would regard 1960 January 1.0 as the dividing point
> between proleptic UTC and UTC, and I would regard proleptic UTC as
> synonymous with UT2.

Does anyone know where SOFA iauDat got its data for 1960 from? Because
that predates the USNO table.

Tony.
-- 
f.anthony.n.finch  <dot at dotat.at>  http://dotat.at/
Plymouth, Biscay: Northwesterly 5 to 7 decreasing 4, then backing
southwesterly 5 or 6 later in Plymouth and northwest Biscay. Moderate or rough
becoming slight or moderate. Showers, thundery at first. Good, occasionally
moderate at first.


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