[LEAPSECS] leapseconds, converting between GPS time (week, second) and UTC

[Steve Allen]

On Tue 2019-01-15T13:10:54-0800 Gary E. Miller hath writ:
> > What is the epoch that was used for TAI?
> "TAI in this form was synchronised with Universal Time at the beginning
> of 1958,"

That is conceptually the case, but even as a concept it deserves
explanation about how it was that the USNO A.1 atomic time scale which
was started with that same epoch differed from the BIH atomic time
scale by 0.035 seconds.

Furthermore, the epoch of A.1 was 1958-01-01T00:00:00 UT2 whereas the
epoch of the BIH atomic time scale was 1958-01-01T20:00:00 UT2, but
this does not explain the difference between the two time scales.

That 1958 epoch is not the basis for the current incarnation of TAI.
Tonight I will scan the pages of Bulletin Horaire with the answer.

--
Steve Allen                    <sla at ucolick.org>              WGS-84 (GPS)
UCO/Lick Observatory--ISB 260  Natural Sciences II, Room 165  Lat  +36.99855
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