[LEAPSECS] BBC radio Crowd Science

michael.deckers michael.deckers at yahoo.com
Wed Feb 1 06:43:44 EST 2017


   On 2017-02-01 05:10, Brooks Harris replied to my
   scribbling:


>>    Actually, there is just one official document
>>    defining UTC (ITU-R Rec 460); plus of course
>>    the Bulletins C of the IERS.

> Generally I agree these are the two most relevant documents. But Rec 460 doesn't
> point you to Bulletin C specifically, IERS has many other products, and the BIPM
> Annual Report on Time Activities looks official, and it is. Its scattered in the
> sense you can't find anything, or, rather, you find many things, and Rec 460
> doesn't say "as per IERS Bulletin C". Only after much research might you
> conclude Bulletin C is the most official, or most important, or most punctual,
> of the IERS products. Even now I'm not completely sure of that, that there isn't
> some other document somewhere....

    Sure, there are many statements about UTC by
    other standardization bodies (BIPM, IERS ISO,..).
    And it can certainly be interesting to know what
    they all have to say. Both IERS Bulletins C and D
    (about DUT1) concern ITU-R Rec 460.

    But I doubt they can say anything authoritatively
    about UTC that is not in ITU-R Rec 460. They
    may well be wrong about it: the ISO C standard
    once allowed for leap second jumps of 2 s, and
    the current ISO SQL standard still allows for it.
    The BIPM made an effort to get the authority
    about UTC (after all, they already have it for
    TAI) but the ITU declined.

    Michael Deckers.


---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus



More information about the LEAPSECS mailing list