On Tue, 2022-10-04 at 20:15 +0000, Michael H Deckers via tz wrote:
On 2022-10-04 19:01, dpatte via tz wrote:
I follow numerous astronomy lists, and there is serious discussion at the IAU (International Astronomical Union) to get rid of leap seconds altogether, and possibly replace them by something else, perhaps leap minutes (or even leap hours) - making them far less common. I believe they expect to make a decision soon, though they have been discussing it for years and had planned to make a decision 2 or 3 years ago.
The BIPM is now in charge, and the CGPM on 2022-11-15..18 in Paris will vote on the proposal D on pages 7..8 and 23..24 in [ https://www.bipm.org/documents/20126/66742098/Draft-Resolutions-2022.p df/2e8e53df-7a14-3fc8-8a04-42dd47df1a04]
Michael Deckers.
The essence of proposal D is: recognizing that the use of UTC as the unique reference time scale for all applications, including advanced digital networks and satellite systems, calls for its clear and unambiguous specification as a continuous time scale, with a well-understood traceability chain, decides that the maximum value for the difference (UT1-UTC) will be increased in, or before, 2035, requests that the CIPM consult with the ITU, and other organizations that may be impacted by this decision in order to − propose a new maximum value for the difference (UT1-UTC) that will ensure the continuity of UTC for at least a century, − prepare a plan to implement by, or before, 2035 the proposed new maximum value for the difference (UT1-UTC), − propose a time period for the review by the CGPM of the new maximum value following its implementation, so that it can maintain control on the applicability and acceptability of the value implemented, − draft a resolution including these proposals for agreement at the 28th meeting of the CGPM (2026), encourages the BIPM to work with relevant organizations to identify the need for updates in the different services that disseminate the value of the difference (UT1-UTC) and to ensure the correct understanding and use of the new maximum value Considering that there has been about one leap second every 18 months, the maximum value for abs(UT1-UTC) would have to be around 60, so this proposal is contemplating leap minutes. Assuming agreement on that value is reached by 2026, there would then be nine years to update everything that depends on abs(UT1-UTC) < 1. One example that comes quickly to mind is the time signals broadcast by WWV, which include the value of UT1-UTC to the nearest 1/10 second, but doesn't have enough space for abs(UT1-UTC) > 1. See https://www.nist.gov/time-distribution/radio-station-wwv/wwv-and-wwvh-digita... I think it would take much longer than nine years to update the WWV transmission format, since that requires updating all consumers of this data. John Sauter (John_Sauter@systemeyescomputerstore.com) -- get my PGP public key with gpg --locate-external-keys John_Sauter@systemeyescomputerstore.com