[LEAPSECS] [Non-DoD Source] D.H. Sadler in 1954

Steve Allen sla at ucolick.org
Sat Mar 17 15:02:54 EDT 2018


On Fri 2018-03-16T16:16:23+0000 Matsakis, Demetrios N CIV NAVOBSY, N3TS hath writ:
> I was surprised to find phrases in the Lick web pages: "CCIR ignored
> the advice that astronomers " and "squelched astronomers who insisted
> that leap seconds would cause trouble".

The IAU publications around the 1970 General Assembly say that.

> GPS, and your local cell towers are all part of the system as well.

One need merely ask everyone with a 4G Android phone in southern
Tasmania whose phone clocks were all an hour off Friday.
http://www.abc.net.au/news/2018-03-16/time-glitch-leaves-some-hobart-residents-an-hour-late/9554758
http://www.dailymail.co.uk/news/article-5508199/Tasmanians-hit-Telstra-phone-glitch-shifted-clocks-back.html

> it looks to me like the switch to UTC was by universal agreement
> among the institutions.  The IAU, URSI, CIPM(=CGPM), and CCIR(= ITU)
> all agreed to the current system in the late 60's, and I would guess
> that the timing of their resolutions probably depended more on the
> (generally) 3-year spacing of their general assemblies than anything
> else.  Note that many of those groups had overlapping membership.  It
> would however be unusual if all individual members of these bodies
> ever agreed to any resolution, even if passed "by consensus".

It looks like some paragraphs about lack of agreement were elided from
the transcriptions of the 1970 IAU General Assembly, but many words
remain that speak of serious disagreeing, ignoring, and excluding.

> For more trivia, the dynamic Gernot Winkler of the USNO was both a
> practical clock man and astronomer.  He was not the only one, and he
> was a very active member of the IAU who chaired commissions, served on
> working groups, etc.  He told me personally that he and Essen
> independently came up with the idea of leap seconds.

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.

The rest of this is nitty gritty details and references with links to
original content so folks can read that.

The documents from the 1970 IAU meeting tell a story which was
witnessed by LEAPSECS contributor Clive Page leaving enough
impression for that to be in his contribution to an art video
https://www.youtube.com/watch?v=GtYvSjS1jUI&t=4m24s

Transactions of the IAU A (1970) (prior to the General Assembly)
Report to Comm 31
http://adsabs.harvard.edu/abs/1970IAUTA..14..343Z
President: F. Zagar
Vice-president: G.M.R. Winkler

Winkler was V.P., and acting president at the General Assembly, yet
the tone of this report to Comm 31 is clearly not in accord with the
actions of the radio broadcast and metrology agencies.

bottom of p.344, the CGPM ignored the 1967 IAU recommendations and
triggered intervention by the IAU president.

middle of p.345, Sadler and Winkler are cited pointing out that an
aircraft Collision Avoidance System cannot tolerate time steps.
Also this sentence has been ignored:
     It is stated as a necessity that activities concering time
     service should be completely independent of the activities of
     frequency laboratories.

bottom of p.345, in 1969 the PTB and URSI asked for a Consultative
Committee on Time Scales to consider the course of action, and CCIR
working party 7 ignored them.  (My impression is that the BIPM/CCTF
Task Group on Time Scale Definitions (TGTSD) which first met in 2016
means that this request was deferred for 47 years.)

Transactions of the IAU B (1971) (at the General Assembly)
Report of Comm 4
http://adsabs.harvard.edu/abs/1971IAUTB..14...79W

p.80, H.M.Smith reported that the CCIR had instituted the leap second,
and D.H.Sadler was strongly opposed.  Also, the IAU had not been
officially informed of the CCIR action to create the leap second.
(The proceedings of the CCIR meetings through 1980 indicate that
H.M.Smith spearheaded the effort to get international agencies and
national laws to adopt the leap second as the perfect solution.)

Report of Comm 31
http://adsabs.harvard.edu/abs/1971IAUTB..14..193W
with last page of that included within
Report of Joint meeting of Comms 4 and 31
http://adsabs.harvard.edu/abs/1971IAUTB..14..198W
Winkler was acting president at these meetings.

p.194 has a break in the flow.  Paragraphs about the perennial
underfunding of the BIH are inexplicably followed by
     The President urged Commission 31 to consider the scope of its
     activities.
and the next paragraph inexplicably switches to H.M.Smith talking
about problems of two time systems.

The second session invited BIPM president J.Terrien to talk about
atomic time scales, something that he followed up later
Metrologia, v8, #3, p.99 (1972)
http://iopscience.iop.org/article/10.1088/0026-1394/8/3/004
     in the last few years regrettable misunderstandings, especially
     between astronomers and physicists, have crept into discussions
     on time and frequency
in a way that seems like sorry, not sorry.

bottom of p.195 has another break in the flow where Winkler reported
that the IAU had received no official communication from the CCIR
about the leap second even though a CCIR resolution had stated the IAU
should be informed.  H.M.Smith said that in the absence of official
word CCIR to IAU there could be no comments from Comm 31.  Smith then
mentions 6 points raised in an earlier meeting.  That seems like it
fits the break in the flow on p.194.  Winkler then stopped discussion
about the CCIR and allowed "free discussion" which is not recorded.

--
Steve Allen                    <sla at ucolick.org>              WGS-84 (GPS)
UCO/Lick Observatory--ISB 260  Natural Sciences II, Room 165  Lat  +36.99855
1156 High Street               Voice: +1 831 459 3046         Lng -122.06015
Santa Cruz, CA 95064           http://www.ucolick.org/~sla/   Hgt +250 m


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