On Fri 2018-08-17T14:07:49-0700 Tom Van Baak hath writ:
> This time I selected Mt Palomar, CA which is
[adding to the typo objections]
known to all astronomers by its proper name "Palomar Mountain"
--
Steve Allen WGS-84 (GPS)
UCO/Lick Observa
the legal time, and NBS was the legal frequency.
--
Steve Allen 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://
e USNO site currently has a broken SSL cert, but the paper is also here
https://www.researchgate.net/publication/323600621_Metrological_and_legal_traceability_of_time_signals
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Steve Allen WGS-84 (GPS)
UCO/Lick Observatory--ISB 260 Natural Sciences II, Room 16
ter there is nothing. I brought it into the lab just to check that
it is still radioactive (wouldn't want to have lost that radium
somewhere). It's the zinc sulfide crystals, the radiation damages
them and they stop producing light.
--
Steve Allen WGS-84 (GPS)
UCO/L
s no longer in use. It was superseded Capitaine et al.
http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2003A%26A...406.1135C
in which formalism it is explicitly disavowed that earth rotation is time.
This is also far afield from the kind of time usually in this group.
--
Steve Allen
On Sat 2019-01-19T12:15:28-0800 Steve Allen hath writ:
> The most expedient place to find them are roughly pages B7 to B12 in a
> current Astronomical Almanac. See for example
> https://babel.hathitrust.org/cgi/pt?id=uc1.31822038913307;view=1up;seq=116
Emphasizing one point, it has al
king, VLBI, pulsar
timing, etc. can measure the effect.
--
Steve Allen 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
depth in the gravitational
potential well. That is how far down you are from Infinity.
The geoid is an equipotential surface.
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Steve Allen WGS-84 (GPS)
UCO/Lick Observatory--ISB 260 Natural Sciences II, Room 165 Lat +36.99855
1156 High Street Voice: +1 831 4
ils/en/pdf/CGPM/Convocation-2018.pdf
The fixed value of the potential means that the rate of TAI is now
defined not to change over geologic time scales as sea level changes.
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Steve Allen WGS-84 (GPS)
UCO/Lick Observatory--ISB 260 Natural Sciences II, Room 165 Lat
cesium vs. Ephemeris
Time for more years than the original papers. In 1964 Anna Stoyko
found a value of the cesium frequency 9192631799 Hz w.r.t. Ephemeris
Time (Bulletin Horaire ser 6 no 7 p 186).
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Steve Allen WGS-84 (GPS)
UCO/Lick Observatory--ISB 260 Natural Sc
evolution
> of accuracy. My Google-fu has failed me in finding anything pre-Atomic.
https://www.ucolick.org/~sla/leapsecs/annastoyko.html
--
Steve Allen WGS-84 (GPS)
UCO/Lick Observatory--ISB 260 Natural Sciences II, Room 165 Lat +36.99855
1156
on earth disciplined oscillators, a treasure chest of
descriptions and diagrams of early circuits and drum recording
devices, and a pile of dirty laundry about who made good and bad
decisions in international agreements about time.
--
Steve Allen WGS-84 (GPS)
UCO/Lick Ob
nd
have been fixed; new rollovers happened around the beginning of this
year.
--
Steve Allen 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 Cr
ely on pendulum clocks, and there are lots of fun
diagrams of early electronics and radio tech too.
--
Steve Allen WGS-84 (GPS)
UCO/Lick Observatory--ISB 260 Natural Sciences II, Room 165 Lat +36.99855
1156 High Street Voice: +1 831 459 3046
ly by scouring
contemporary publications for quotes from many folks who were present
does it begin to become clear how much that attitude prevented clear
description of the history.
--
Steve Allen WGS-84 (GPS)
UCO/Lick Observatory--ISB 260 Natural Sciences II, R
cause it is painfully
evident where there were typos and where some integration went awry
for several points before returning to match again. Not possible to
see, of course, are cases where the numbers went awry and stayed
that way.
--
Steve Allen WGS-84 (GPS)
o use just plain UT for things on earth, and
ET (now relativisticly TT, or TCB, or TDB) for things not on earth.
The principal printed appearance of new-UTC was in decrees from
bureaucrats who were protected from seeing that the pracitioners of
time did not agree that new-UTC was the best thing to use for
e kept in the observer's head while
marking the log book, and in the dark the big minute hand was a big
help to a lone observer whose hands and nose were freezing while
guiding the telescope by eye and slewing it to the next target by
hand.
--
Steve Allen WGS-84 (GP
4-19.pdf
The current version ITU-R TF.460-6 says that time signals should
not deviate by more than 1 ms from UTC.
How can these broadcasts justify such a large offset?
--
Steve Allen WGS-84 (GPS)
UCO/Lick Observatory--ISB 260 Natural Sciences II, Room 165 Lat +36.9
,
and we have reconfigured the critical machines to use local servers.
Has anyone else seen a degradation of reachability and delay to NTP pool?
--
Steve Allen WGS-84 (GPS)
UCO/Lick Observatory--ISB 260 Natural Sciences II, Room 165 Lat +36.99855
1156 High Street
e company who are at
least being paid to address the problem.
--
Steve Allen 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
I have taken a much deeper dive through the history of geophysics
and upon coming up for air...
On Fri 2020-05-15T22:02:32-0700 Steve Allen hath writ:
> On Fri 2020-05-15T21:49:43-0700 Tom Van Baak hath writ:
> > Also, some of the very best pendulum clocks ever made were go
le enough optical network
to measure the changing difference in their potentials.
--
Steve Allen 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
ntinental Triangulation and the American Arc of the Parallel
Assistant CHAS. A. SCHOTT, Chief of the Computing Division, USC
ftp://ftp.library.noaa.gov/docs.lib/htdocs/rescue/cgs_specpubs/QB275U35no41900.pdf
--
Steve Allen WGS-84 (GPS)
UCO/Lick Observatory--ISB 260
rvatory hosted one of the sites in 1888. google will reveal scans
of a lot of the preliminary reports for the traverse in parts farther
east.
--
Steve Allen WGS-84 (GPS)
UCO/Lick Observatory--ISB 260 Natural Sciences II, Room 165 Lat +36.99855
1156 High Street
crystals
http://adsabs.harvard.edu/full/2004ESASP.544..131A
One of them has failed, and they were never always on, in which case
the aux osc are other crystals
https://descanso.jpl.nasa.gov/DPSummary/Descanso4--Voyager_new.pdf
--
Steve Allen WGS-84 (GPS)
UCO/Lick Ob
uot;garde-temps") were kept
27 m below ground in caves and galleries which were part of the
Paris catacombs.
Various issues of Bulletin Horaire report discontinuities in the
operation of those clocks due to distant earthquakes.
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Steve Allen WGS-84 (GP
ot perceivable (~100ms).
> At least in Europe.
Did everyone involved in designing the hardware and software
intend that phone to have precise time?
https://www.jwz.org/blog/2010/07/what-at-t-doesnt-run-ntpd/
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Steve Allen WGS-84 (GPS)
UCO/Lick Observatory--ISB
y measurement to determine the offset of the chronometer was
using a sextant to shoot a lunar and determine the time based on the
angle between moon and star.
--
Steve Allen WGS-84 (GPS)
UCO/Lick Observatory--ISB 260 Natural Sciences II, Room 165 Lat +36.99855
1156 High
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