On Fri 2020-11-13T16:43:14-0800 Guy Harris hath writ:
So what documents indicate how UTC was implemented prior to 1972-01-01 00:00:00 UTC?
The source documents for the practice are the publications of the Bureau International de l'Heure, namely Bulletin Horaire through 1966 and Circular D after that. See the index of issues https://www.ucolick.org/~sla/leapsecs/bhissues.html Within those issues are references to the international agreements which BIH was tasked to implement, and a lot more nitty gritty. detail than is found in wikipedia or any summary.
And what documents discuss the changeover to "new" UTC (decision made in 1970 to start "new UTC' in 1972?)?
The source documents are from the BIH, CCDS, CIPM, CGPM, IAU, URSI, CCIR, IEEE, etc., and also memoirs of the dramatis personae at those meetings. Again, no summary tries to capture the whole story, and it is evident that details were redacted from the public proceedings.
And, for anybody who cares in that much detail about the definition of the Epoch, should 1970-01-01 00:00:00 UTC be interpreted as *literally* being 1970-01-01 00:00:00 UTC, or as 1970-01-01 00:00:00 "new UTC extended backwards", i.e. "TAI, and new UTC extended backwards, were 10 seconds apart from the beginning of TAI all the way up to 1972-06-30 23:59:59, and then new UTC started getting leap seconded"?
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