On 2018-03-17 19:02, Steve Allen wrote:
I am going to have to stop being amazed when I keep learning of yet
another person taking credit for inventing the leap second. The 1970
IAU documents indicate that Winkler was one who warned that leap
seconds would cause trouble for automated systems. They also make it
clear that there was not unanimity, and that there was overlap.
[McCarthy 2009. p 228] states that leap seconds in UTC was an idea
"introduced independently by Louis Essen and Gernot Winkler". It just
was a variation of "Stepped Atomic Time" (SAT) that had gained some
usage at the time, and was known to be practicable.
Regardless of the amount of disagreement among astronomers then, there
certainly seems to be some _current_ disagreement among astronomers
about
the future of UTC -- should leap seconds be omitted in the future so
that UTC becomes a continuous time scale, or should we keep the current
limit of |UT1 - UTC|?
The current proposal [BIPM 2018. p 11..13, 32..33] for Resolution B
of the
General Conference of Weights and Measures 2018 makes UTC a time scale
"produced by the BIPM" and recommends a revision of the limit |UT1 -
UTC|.
While the proposed Resolution does recommend work on improved
dissemination
of UT1 - UTC, it does not say anything about the dissemination of
TAI - UTC.
So, the likely future is that the limit on |UT1 - UTC| will be dropped,
leap seconds will no longer be applied, and UTC will become a fixed
translate of TAI (so that dissemination of TAI - UTC becomes
unnecessary).
Hence, people [astronomers?] interested in keeping the current
definition
of UTC should strive for improved dissemination of TAI - UTC, so as to
make a continuous time scale easily accessible (for example,
together with
NTP time signals). The knowledge of current UTC, as a compromise between
TAI and UT1, is, in the long term, obviously of less value than the
knowledge
of both UT1 and TAI together; the short term advantage of using UTC
may only
lie in the fact that it may be easier to newly disseminate TAI - UTC
with UTC
values than to extend the dissemniation of UTC to values of UT1 - UTC
exceeding 1 s.
[BIPM 2018] CGPM26 convocation: draft Resolution B
[https://www.bipm.org/utils/en/pdf/CGPM/Convocation-2018.pdf]
[McCarthy 2009] Dennis D McCarthy, P Kenneth Seidelmann: "Time -- From
Earth Rotation to Atomic Physics". Wiley-VCH Verlag. 2009 Weinheim.
ISBN 978-3-527-40780-4.
Michael Deckers.
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