Re: what time is it, legally?
In message <[EMAIL PROTECTED]>, "Daniel R. Tobias" writes: >> http://gauss.gge.unb.ca/papers.pdf/gpsworld.january01.pdf > >One quibble with that article is that it gives the Global Positioning >System as an example of how humanity has been obsessed with knowing >what time it is. Actually, GPS arises from our obsession with >knowing what *place* we're at; its need for precise time is a mere >technical detail of its implementation. Absolutely not true. The original military requirements for GPS demanded timetransfer better then 10 microseconds for safe comms purposes. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [EMAIL PROTECTED] | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.
Re: what time is it, legally?
- Original Message - From: "Daniel R. Tobias" <[EMAIL PROTECTED]> To: Sent: Thursday, December 14, 2006 5:45 AM Subject: Re: [LEAPSECS] what time is it, legally? > On 13 Dec 2006 at 21:43, Steve Allen wrote: > > > http://gauss.gge.unb.ca/papers.pdf/gpsworld.january01.pdf > > One quibble with that article is that it gives the Global Positioning > System as an example of how humanity has been obsessed with knowing > what time it is. Actually, GPS arises from our obsession with > knowing what *place* we're at; its need for precise time is a mere > technical detail of its implementation. (Some of the earlier > historical needs for precise time also arose out of navigation, where > knowing one's position in space necessitated also knowing something > about time.) > All through this debate I've been struck by the parallels to the story of John Harrison as described in Dava Sobel's _Longitude_. Like Harrison's clocks, GPS provides both time and longitude for those with the means to process the needed information out of the raw data. And, like the 18th-century debate between astronomers and "mechanics" (clockmakers), over observational vs. synthetic means of determining position in space and time, we now have a debate between those who believe our notions of time MUST remain astronomically based and those who see more precise (and more easily managable) oscillators--cesium atoms--as being the wisest choice for current and future scientific purposes. What the outcome of this will be, and who will be interested in any of this discussion 250 years from now, remains to be seen, but the effects on future timekeeping and related endeavors will most likely be just as significant. The upshot: be careful what you say, gentlemen; someday, a descendent of Sobel's may write a book about _you_! :) Brian Garrett
Re: what time is it, legally?
On Thu 2006-12-14T08:45:12 -0500, Daniel R. Tobias hath writ: > Actually, GPS arises from our obsession with > knowing what *place* we're at; its need for precise time is a mere > technical detail of its implementation. I am often amused by online complaints that someone's handheld GPS has the time wrong by two seconds. I surmise that with such units it is also the case that the position it gives is correct for where it was two seconds ago. One thing that is clear from Levine's article is that you get what you pay for, and that if you really want it done well you have to pay lots. What I don't understand is why this does not generalize to leap seconds. -- Steve Allen <[EMAIL PROTECTED]>WGS-84 (GPS) UCO/Lick ObservatoryNatural Sciences II, Room 165Lat +36.99858 University of CaliforniaVoice: +1 831 459 3046 Lng -122.06014 Santa Cruz, CA 95064http://www.ucolick.org/~sla/ Hgt +250 m
Re: what time is it, legally?
>From its outset, GPS was intended to provide position, velocity and time (PVT). In some of his public talks, one of the people credited with inventing GPS, Brad Parkinson, renames GPS to GPtS to drive the point home that it is a positioning and timing service. -- Richard Langley On Thu, 14 Dec 2006, Daniel R. Tobias wrote: >On 13 Dec 2006 at 21:43, Steve Allen wrote: > >> http://gauss.gge.unb.ca/papers.pdf/gpsworld.january01.pdf > >One quibble with that article is that it gives the Global Positioning >System as an example of how humanity has been obsessed with knowing >what time it is. Actually, GPS arises from our obsession with >knowing what *place* we're at; its need for precise time is a mere >technical detail of its implementation. (Some of the earlier >historical needs for precise time also arose out of navigation, where >knowing one's position in space necessitated also knowing something >about time.) > >-- >== Dan == >Dan's Mail Format Site: http://mailformat.dan.info/ >Dan's Web Tips: http://webtips.dan.info/ >Dan's Domain Site: http://domains.dan.info/ > === Richard B. LangleyE-mail: [EMAIL PROTECTED] Geodetic Research Laboratory Web: http://www.unb.ca/GGE/ Dept. of Geodesy and Geomatics EngineeringPhone:+1 506 453-5142 University of New Brunswick Fax: +1 506 453-4943 Fredericton, N.B., Canada E3B 5A3 Fredericton? Where's that? See: http://www.city.fredericton.nb.ca/ ===
Re: what time is it, legally?
On 13 Dec 2006 at 21:43, Steve Allen wrote: > http://gauss.gge.unb.ca/papers.pdf/gpsworld.january01.pdf One quibble with that article is that it gives the Global Positioning System as an example of how humanity has been obsessed with knowing what time it is. Actually, GPS arises from our obsession with knowing what *place* we're at; its need for precise time is a mere technical detail of its implementation. (Some of the earlier historical needs for precise time also arose out of navigation, where knowing one's position in space necessitated also knowing something about time.) -- == Dan == Dan's Mail Format Site: http://mailformat.dan.info/ Dan's Web Tips: http://webtips.dan.info/ Dan's Domain Site: http://domains.dan.info/
Re: what time is it, legally?
On Tue 2006-12-12T09:18:57 -0400, Richard B. Langley hath writ: > For an overview of some of the legal issues of time see "GPS and the Legal > Traceability of Time" by Judah Levine in my GPS World Innovation column, > January 2001. > -- Richard Langley >Professor of Geodesy and Precision Navigation >and Contributing Editor, GPS World Magazine viz http://gauss.gge.unb.ca/papers.pdf/gpsworld.january01.pdf -- Steve Allen <[EMAIL PROTECTED]>WGS-84 (GPS) UCO/Lick ObservatoryNatural Sciences II, Room 165Lat +36.99858 University of CaliforniaVoice: +1 831 459 3046 Lng -122.06014 Santa Cruz, CA 95064http://www.ucolick.org/~sla/ Hgt +250 m
Re: what time is it, legally?
On Dec 12, 2006, at 5:56 PM, [EMAIL PROTECTED] wrote: To avoid such failures in the future, Tom Van Baak has agreed to take over its management and he is now working on the technical issues involving the migration. Thanks for looking into that. Thanks to Tom for accepting another (nearly) thankless chore. Thanks to everybody who checked their mail folders. I'm relieved to find the issue appears archival only, not a problem with the initial distribution. Would hate to think of all of you being deprived of my pellucid wisdom :–) Rob
Re: what time is it, legally?
From: Peter Bunclark <[EMAIL PROTECTED]> Subject: Re: [LEAPSECS] what time is it, legally? Date: Wed, 13 Dec 2006 10:05:00 + Message-ID: <[EMAIL PROTECTED]> Rob, > On Wed, 13 Dec 2006, Ed Davies wrote: > > > Rob Seaman wrote: > > > I'm given to wonder how much of the friction on this mailing list is > > > simply due to the shortcomings in the technology that implements it. > > > I've appended a message I sent in August with four plots attached. Can > > > someone tell me whether it is readable now or was successfully delivered > > > back then? I rummaged around on the list archive and on archives > > > accessibly via google and find no copy of this message that survived the > > > communications medium. > > > > In Thunderbird on Ubuntu Linux it looked fine in both your original > > post and the repeat you attached - so any problems are down to the > > reader and not the transmission, I think. > > > > Ed. > > > Fine on Solaris 10. I concurr, it worked nice on Debian Linux using Mew in Emacs. I had nice graphs and everything. You need to look elsewere (i.e. more locally) to find the fault. Cheers, Magnus
Re: what time is it, legally?
On Wed, 13 Dec 2006, Ed Davies wrote: > Rob Seaman wrote: > > I'm given to wonder how much of the friction on this mailing list is > > simply due to the shortcomings in the technology that implements it. > > I've appended a message I sent in August with four plots attached. Can > > someone tell me whether it is readable now or was successfully delivered > > back then? I rummaged around on the list archive and on archives > > accessibly via google and find no copy of this message that survived the > > communications medium. > > In Thunderbird on Ubuntu Linux it looked fine in both your original > post and the repeat you attached - so any problems are down to the > reader and not the transmission, I think. > > Ed. > Fine on Solaris 10. Pete.
Re: what time is it, legally?
Rob Seaman wrote: I'm given to wonder how much of the friction on this mailing list is simply due to the shortcomings in the technology that implements it. I've appended a message I sent in August with four plots attached. Can someone tell me whether it is readable now or was successfully delivered back then? I rummaged around on the list archive and on archives accessibly via google and find no copy of this message that survived the communications medium. In Thunderbird on Ubuntu Linux it looked fine in both your original post and the repeat you attached - so any problems are down to the reader and not the transmission, I think. Ed.
Re: what time is it, legally?
My few-month old mac gives me a message saying "This attachment is a type not yet supported" I also get this problem on my XP at home but not on the one at my office. A newphew of mine forwarded me the reason once, and it is related to shortcuts in the email bit-pattern. I forget which software is at fault. I want to apologize for any and all technological failures of this listserve. To avoid such failures in the future, Tom Van Baak has agreed to take over its management and he is now working on the technical issues involving the migration. Demetrios Matsakis -Original Message- From: Leap Seconds Issues To: LEAPSECS@ROM.USNO.NAVY.MIL Sent: 12/12/2006 7:14 PM Subject: Re: [LEAPSECS] what time is it, legally? I'm given to wonder how much of the friction on this mailing list is simply due to the shortcomings in the technology that implements it. I've appended a message I sent in August with four plots attached. Can someone tell me whether it is readable now or was successfully delivered back then? I rummaged around on the list archive and on archives accessibly via google and find no copy of this message that survived the communications medium. On Dec 12, 2006, at 2:17 PM, Tom Van Baak wrote: > Is there a technical definition of the "mean" in "mean solar > time" that would help guide the discussion? See the appended message. There appears to be a natural excursion of several minutes even in the absence of first order lunar effects in accumulated "leap" offset over the course of several centuries. Undoubtedly an expert could wax poetic on this subject should one care to speak up. Perhaps this natural variability could be used to start to wrestle with the issue. > One could argue that adding 50 or 100 leap milliseconds a > few times a year (as was done in the 60's) to preserve the > mean is just as valid as adding a couple of leap seconds > every few years (as is done now) is just as valid as adding > a couple leap hours every few thousand years (as has been > proposed). I'm with you for the first two, but not the third. An approximation that is as large as the width of a timezone is equivalent to eliminating timezones. > I'm not arguing for one over the other but it seems to me > all three models achieve a mean. See my previous message. (Assuming it was delivered.) > None of them prevent secular drift. Secular means you never zero it out. Pretending that we can get away with that is where the ALHP fails. Rob -- Begin forwarded message: > From: Rob Seaman <[EMAIL PROTECTED]> > Date: August 5, 2006 6:47:29 PM MST > To: Leap Seconds Issues > Subject: Re: trading amplitude for scheduling > > John Cowan wrote: > >> Rob Seaman scripsit: >> >>> Third result - even in the absence of lunar braking, leap jumps >>> (or equivalent clock adjustments) would remain necessary. >> >> Why is that? >> >> If the SI second were properly tuned to the mean solar day, and the >> secular slowing were eliminated, there would be no need to mess >> about with >> the civil time scale, because the random accelerations and >> decelerations >> would cancel out in the long run. Of course, we'd have to >> tolerate larger >> differences between clock time and terrestrial time, but we'd >> expect that. > > Excellent discussion. The answer depends on how much larger the > clock differences are, and on the meaning of the word "tolerate". > As Tom Van Baak said: > >> My understanding is that, in addition to astronomical >> effects (lunar/solar tides), no small number of geological >> and climatological phenomena also contribute to the >> instability of the mean solar day. That all the random >> accelerations exactly cancel all the random decelerations >> in any finite time, short- or long-term, is very unlikely. > > Which is to say that "proper tuning" may not even have a > definition. It certainly is non-trivial. > > Consider the historical trend (from http://www.ucolick.org/~sla/ > leapsecs/dutc.html): > ? > Detrend the data by removing the 1.7 ms/cy secular effect: > ? > (I read the LOD from the plot every century - should repeat with > the original data, but results should be acceptably accurate. I'm > sure somebody would be happy as a clam to point out any errors I > may have made :-) > > There are positive and negative excursions from "normal" that > persist for centuries. For the purpose of civil timekeeping, we > don't care what geophysics causes these excursions, or even whether > the rather evident sinusoid is real or not, but just that the > residual ~ +/- 5 ms length-of-day variations exist. > > Leap seconds represent the accumulation of these daily residuals: > ? > A very small daily residual becomes +/- 9 minute descrepancy > between TAI and UTC over millennial time periods. So even in the > absence of the secular trend, the natural geophysical irascibility > of the planet is very evident. Leap seconds - both positive and > negative, of course - would be needed to resync the clocks.
Re: what time is it, legally?
On Dec 12, 2006, at 1:57 PM, M. Warner Losh wrote:
I view the same data differently. I see it as a progression:
Local Solar time -> mean local solar time ->
timezone as mean local time at one point used for many -> UTC
-> ???
Clearly, we're moving away from solar time and towards something else.
Only if you successfully make that last leap into the unknown.
Rather, clearly we've refined our understanding of solar time over
the last couple of centuries. As demonstrated previously, all
parties agree (even if they don't agree that they agree :–) that
short of some "caves of steel" science fiction scenario, civil time
must mimic mean solar time closely. We disagree over the definition
of "closely", but it is better than one second per day unless one
chooses to pretend that our "customers" – that is, all the citizens
of all the countries of the world – would suffer a leap hour every
decade (365 x 10 > 3600s). Consider that this one second (or much
tighter) tolerance is almost two orders of magnitude smaller than the
annual variation in the length of the apparent solar day.
From my point of view, "closely mimic" should be regarded as "is" –
that is, as a mathematical identity, not just a boundary condition to
be met by forcing equality once every millennium. On the other hand,
the precision timekeepers who proposed the absurd leap hour proposal
apparently deem a few milliseconds per day secular trend as being
tolerable slop. (Rather strange coming from technologists who dote
on nanoseconds.) My position is:
Civil Time == Mean Solar Time (i.e., "time-of-day")
The time lords assert:
Civil Time = Mean Solar Time + epsilon ("something masquerading as
time-of-day")
Which begs the question of what Civil Time is, if it ain't MST but
must be approximated so.
The mere fact of the ALHP arising among those who clearly loathe leap
seconds is a tacit admission that mean solar time rules now – and
will continue to do so in the future. The leap seconds don't get
legislated out of existence, after all, they are merely embargoed for
several centuries. The proponents of the ALHP are not suggesting a
way to escape from this constraint, rather they are acknowledging it
precisely by the form of their Machiavellian non-proposal.
One might suggest that if 1) the ALHP were taken off the table such
that we didn't have to keep batting the smelly thing away, and 2) its
proponents would deign to participate in a dialog, then 3) progress
might actually be made on solving the real problem of conveying BOTH
interval time AND time-of-day to the precision time users (i.e.,
"people") of the world.
It isn't revolutionary to suggest that you look before you leap
(http://en.wikipedia.org/wiki/Precautionary_principle).
Rob Seaman
NOAO
Re: what time is it, legally?
From: Steve Allen <[EMAIL PROTECTED]> Subject: [LEAPSECS] what time is it, legally? Date: Mon, 11 Dec 2006 20:45:58 -0800 Message-ID: <[EMAIL PROTECTED]> > This history is apparently not lost to folks at NIST, for the US > senate continues to consider legislation which would explicitly > rewrite US legal time to be based on UTC (as locally interpreted) > rather than Greenwich mean solar time. The most recent incarnation of > the bill appeared in September as S3936, and section 1406 contains the > text to make the change. See at > http://thomas.loc.gov/cgi-bin/query/z?c109:S.3936.PCS: > (and note the trailing colon in the URL). > > The bill has a lot of cosponsors as seen in the links on Thomas. > Clearly the passage of this bill would short circuit a litigation > process which the Jenni Parrish document shows to have lasted for most > of a lifetime. Sounds like a good thing. Here in Sweden, Swedish Normal Time is by law defined to be UTC + 1h. Both UTC and BIPM is explicitly mentioned in the law (SFS 1979:988). Swedish summertime is a little bit fuzzier, but UTC + 2h is a valid interpretation. There is 8 NTP servers being under the control of the national metrological institute SP. Those servers traces back to the national laboratory, redundant, has backup power for as long as we care. However, there is actually no legal path to get traceable time. It is not only necessary to have legal time defined as UTC, you also need the legal tools which enables legal supported (and required) traceability, so that definition actually means something. When reading up on the issue and talking to the national accreditation boards cheif lawyer, I was not only supprised about the loophole, but the view the accreditation board feeling not empowered to address the issue besides for "customer concerns". Sigh. Let's just say that I was less than happy with the situation. Work is under way to remedy that issue. Now, how is the situation elsewhere? Is the legal definition followed up with the legal tools to also do traceability of time (and not just SI second)? Cheers, Magnus
Re: what time is it, legally?
> But this needs a clarification. Standard time replaced local > apparent solar time in several steps. First, clock (mean) time > replaced apparent time for civil purposes. As you can see from the > proliferation of railroad standards, these were both still local to > one place or another. Later, local time was referenced to standard > localities such as Greenwich. Still later, a loose international > consensus was formed regarding a common time zone system with a > single standard prime meridian. > > All of these remained solar time. Mean solar time of some remote > location is still a flavor of solar time because there is no secular > drift. The important issue is the continuity of still recognizing > mean solar time as the foundation of civil time. Leap seconds are > simply one possible mechanism for achieving this. The notion of a > leap hour fails to preserve mean solar time in any practical fashion. > > Rob Seaman > NOAO Rob, Is there a technical definition of the "mean" in "mean solar time" that would help guide the discussion? One could argue that adding 50 or 100 leap milliseconds a few times a year (as was done in the 60's) to preserve the mean is just as valid as adding a couple of leap seconds every few years (as is done now) is just as valid as adding a couple leap hours every few thousand years (as has been proposed). I'm not arguing for one over the other but it seems to me all three models achieve a mean. All prevent noon drifting to midnight. All are a form of solar time. None of them scale well to the extreme past or the extreme future. All of them have practical limitations. None of them prevent secular drift. /tvb
Re: what time is it, legally?
I view the same data differently. I see it as a progression: Local Solar time -> mean local solar time -> timezone as mean local time at one point used for many -> UTC -> ??? Clearly, we're moving away from solar time and towards something else. Our ability to tell time has exceeded the earth's ability to be perfectly periodic. The time will come when we need to change something as the current system is doomed to failure, sooner or later. I feel that attempts to tie time to the sun and to also have a precice notion of a second are fundamentally at odds with one another and the current system tries very hard to paper over the differences. No doubt they can be papered over for years to come, but the basic physics of platentary rotation with a large satellite stand against it. I'm unsure what that "something else" should be, and I'm not sure that we're in a good position to know with certainty what would be a good solution. I just know that invoking variable radix counting schemes has its limitations and difficulties... Anyway, I know others view it differently, but if it was easy and obvious there wouldn't be such a divergence of opinion, eh? Warner
Re: what time is it, legally?
Rob Seaman wrote: >But this needs a clarification. Standard time replaced local >apparent solar time in several steps. Quite so. I glossed over this. The practicalities evolved, and so did the solutions deployed. The trend has been consistently for increasing globalisation and (except for DST) predictability. >All of these remained solar time. Mean solar time of some remote >location is still a flavor of solar time because there is no secular >drift. Mm. I'm wondering how fundamental an aspect that is. If a need arises for a timescale shared between multiple planets then, projecting the same processes, parochial planetary rotation would not remain a feature of the compromise system. But perhaps the same processes don't apply beyond the planetary level. Perhaps Earth rotation time is not so much a particular (type of) timescale that can be used in this process but rather the context within which the process operates. The whole story that we have looked at here has been about time of day. Presumably the same processes can operate on interval timescales, as well as time-of-day timescales. In this context, all these flavours of solar time *are* just steps on the way. The next step on this path is to diverge from the time-of-day path. >The important issue is the continuity of still recognizing >mean solar time as the foundation of civil time. That is, civil time has been identified with time of day throughout this process. I don't think it need remain so indefinitely. -zefram
Re: what time is it, legally?
On Dec 12, 2006, at 11:46 AM, Poul-Henning Kamp wrote: I think that the most and possibly only bit of relevance to contemporary issues in this legal summary is that time has to be available to people to legally bind them. I agree that the precise issues differ today, but surely the potential (and more than potential) legal timekeeping entanglements are much more complex. Certainly the money riding on possible timekeeping snafus is orders of magnitude greater. Split seconds can represent fortunes on Wall Street. I interpret this as trying to trick somebody with the TAI-UTC difference would be a no-go with The Supremes. Cases that rise to the level of the Supreme Court tend to focus on ambiguities intrinsic in the interpretation of conflicting statutes or gray areas in the Constitution. Rarely would mere "tricks" get past a lower appellate court. The natural distinction between TAI (interval time) and UTC (time-of- day) is in danger of becoming obscured. One would expect this increased ambiguity to generate more significant legal challenges, not fewer. Rob Seaman NOAO
Re: what time is it, legally?
I think that the most and possibly only bit of relevance to contemporary issues in this legal summary is that time has to be available to people to legally bind them. You simply can't stipulate a deadline on a timescale they do not have access to, and the legal basis for this argument seems to be "right to a fair trial". I interpret this as trying to trick somebody with the TAI-UTC difference would be a no-go with The Supremes. But what the timescale is, who owns it or who controls is clearly a legislative issue according to the most recent rulings. But interesting reading, all the same. -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [EMAIL PROTECTED] | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.
Re: what time is it, legally?
On Dec 12, 2006, at 9:38 AM, Zefram wrote: ...a lot of stuff I agree with. Standard timezones have replaced solar time in general use But this needs a clarification. Standard time replaced local apparent solar time in several steps. First, clock (mean) time replaced apparent time for civil purposes. As you can see from the proliferation of railroad standards, these were both still local to one place or another. Later, local time was referenced to standard localities such as Greenwich. Still later, a loose international consensus was formed regarding a common time zone system with a single standard prime meridian. All of these remained solar time. Mean solar time of some remote location is still a flavor of solar time because there is no secular drift. The important issue is the continuity of still recognizing mean solar time as the foundation of civil time. Leap seconds are simply one possible mechanism for achieving this. The notion of a leap hour fails to preserve mean solar time in any practical fashion. Rob Seaman NOAO
Re: what time is it, legally?
Steve Allen wrote: >http://www.uakron.edu/law/docs/parrish36.1.pdf Interesting. What this shows, to me, is that timescales are chosen bottom-up: legislation doesn't really work. People choose a timescale according to their needs at the time. At the start of the narrative people used local solar time, because that was readily available, unlike clock time. Later on railways and businesses adopted a common standard, because of their needs to synchronise, and for a long time this coexisted peacefully with the customary use of solar time in other spheres of activity. Having two timescales in common use caused some legal problems in situations where a law or contract failed to specify timescale; this is a familiar problem. Standard timezones have replaced solar time in general use because of an increased practical need for standardisation, and the law followed general use, it did not lead. The only point in the story where legislation innovates is in the introduction of DST. That appears to have met with a lot of resentment from people who wanted to continue using whatever timescale they judged most appropriate for them. I conclude that attempts to impose a fundamental change in UTC are doomed. Those who want a timescale without leap seconds will use one (indeed there are some widespread uses of TAI), and it will displace UTC iff the public finds it convenient. Legal time might change from UT (of any flavour) to TAI or TAI+offset, but only in response to popular usage. >I have not counted whether the majority of cases were about >the time of liquor sales (an issue which had been resonating >throughout the US for all of the same interval of time) or >about contractual obligations of insurers. Insurance cases were the plurality. >http://home.tiscali.nl/annejan/swf/timeline.swf I like it. Brings out some inportant features of time units and our position with respect to them. What does it do at a leap second? -zefram
Re: what time is it, legally?
Richard B. Langley wrote: For an overview of some of the legal issues of time see "GPS and the Legal Traceability of Time" by Judah Levine in my GPS World Innovation column, January 2001. Levine has a powerpoint on the same topic: http://www.navcen.uscg.gov/cgsic/meetings/summaryrpts/36thmeeting/ Presentations/levine.ppt Rob
Re: what time is it, legally?
For an overview of some of the legal issues of time see "GPS and the Legal Traceability of Time" by Judah Levine in my GPS World Innovation column, January 2001. -- Richard Langley Professor of Geodesy and Precision Navigation and Contributing Editor, GPS World Magazine On Mon, 11 Dec 2006, Steve Allen wrote: >Longtime readers of LEAPSECS will remember that in the wake of the >Torino colloquium we started joking about legal implications of civil >time in the absence of leap seconds. This was before the Internet >Mail Archive started recording the content of the list, and due to >issues at USNO it was among the correspondence lost to the official >archive as well. I have had it online at >http://www.ucolick.org/~sla/leapsecs/reductio.html > >I ran across a rather lengthy article by Jenni Parrish of UC Hastings >College of Law in the Akron Law Review. >http://www.uakron.edu/law/docs/parrish36.1.pdf >It is 47 pages of legal history regarding litigation in the US (and >also a seminal case in the UK) during the advent of standard time. >It is copiously footnoted with source references. > >I have not counted whether the majority of cases were about >the time of liquor sales (an issue which had been resonating >throughout the US for all of the same interval of time) or >about contractual obligations of insurers. >The bottom line is that the discussion in LEAPSECS was no joke, for >people really did engage in court cases about the time on the clock. > >This history is apparently not lost to folks at NIST, for the US >senate continues to consider legislation which would explicitly >rewrite US legal time to be based on UTC (as locally interpreted) >rather than Greenwich mean solar time. The most recent incarnation of >the bill appeared in September as S3936, and section 1406 contains the >text to make the change. See at >http://thomas.loc.gov/cgi-bin/query/z?c109:S.3936.PCS: >(and note the trailing colon in the URL). > >The bill has a lot of cosponsors as seen in the links on Thomas. >Clearly the passage of this bill would short circuit a litigation >process which the Jenni Parrish document shows to have lasted for most >of a lifetime. > >To end with some fun, here's a Flash clock application >http://home.tiscali.nl/annejan/swf/timeline.swf > >-- >Steve Allen <[EMAIL PROTECTED]>WGS-84 (GPS) >UCO/Lick ObservatoryNatural Sciences II, Room 165Lat +36.99858 >University of CaliforniaVoice: +1 831 459 3046 Lng -122.06014 >Santa Cruz, CA 95064http://www.ucolick.org/~sla/ Hgt +250 m > === Richard B. LangleyE-mail: [EMAIL PROTECTED] Geodetic Research Laboratory Web: http://www.unb.ca/GGE/ Dept. of Geodesy and Geomatics EngineeringPhone:+1 506 453-5142 University of New Brunswick Fax: +1 506 453-4943 Fredericton, N.B., Canada E3B 5A3 Fredericton? Where's that? See: http://www.city.fredericton.nb.ca/ ===
