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U.S. Scientists Call for a Time Change 465

Posted by CmdrTaco from the this-is-gonna-get-tricky dept.
saqmaster writes "The BBC reported yesterday that U.S. scientists want to change the current system which keeps clocks in sync with solar time by adding a leap second every 18 months or so. This has rattled a few cages with the scientists and operators involved in GMT-related projects and facilities as it would effectively remove the importance of the meridian from timing. "
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U.S. Scientists Call for a Time Change More

U.S. Scientists Call for a Time Change

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  • It about time! (Score:5, Funny)

    by thewiz ( 24994 ) * on Thursday November 10, 2005 @07:02PM (#14002902)
    No, really, it is about time.

  • In related news (Score:5, Funny)

    by A beautiful mind ( 821714 ) on Thursday November 10, 2005 @07:05PM (#14002934)
    From the article:"They want for the first time in history to separate us from the natural rotation of the Earth, which means as the years go by we will increasingly get out of sync with astronomy and the real world,"

    In other news, residents of Kansas experienced a timeshift, time going back to 1213 AD.

    • Re:In related news (Score:5, Funny)

      by Tackhead ( 54550 ) on Thursday November 10, 2005 @07:14PM (#14003026)
      > > They want for the first time in history to separate us from the natural rotation of the Earth, which means as the years go by we will increasingly get out of sync with astronomy and the real world,"
      >
      > In other news, residents of Kansas experienced a timeshift, time going back to 1213 AD.

      Oh, that's simple to explain. Kansas moved one state to the right - meaning they're no longer on CST, but on EST: Enlightenment Savings Time.

    • Why? (Score:5, Funny)

      by Anonymous Coward on Thursday November 10, 2005 @07:51PM (#14003339)
      Why are you attacking Kansas? We are good God Fearing Christians who are carrying out His Will. I honestly do not get why some people feel the need to persecute Christians. At least you people aren't using lions.

  • Just call it stardate (Score:5, Funny)

    by Bastard of Subhumani ( 827601 ) on Thursday November 10, 2005 @07:05PM (#14002936) Journal
    Just call it stardate, everyone will love it. Well, everyone here, anyway.

  • Time should be decided by the UN (Score:5, Funny)

    by the_skywise ( 189793 ) on Thursday November 10, 2005 @07:06PM (#14002948)
    Since this is a "world" resource, time should no longer be managed by the UK, but by the UN standards body. Surely this will be a much more equitable and fair solution than hogging all of the world's time by one nation.

    (Near as I can tell, it's either a tit for tat for the internet thing, or Verizon and SBC have ponied up some big lobbyist dollars to save themselves a few seconds of headache every few years (ha) )
  • That we need to add a second every 18 months is obvious evidence that our time system is just too complex to have simply happened, and is therefore indicative of an intelligence in time design.

    This post brought to you from the Kansas Board of Edumacation.

  • Why not adopt a universal ttime? (Score:5, Insightful)

    by greymond ( 539980 ) on Thursday November 10, 2005 @07:07PM (#14002965) Homepage Journal
    Why not just forget about time zones, day light savings and create a new universal global time. So what if it makes my 8am-5pm job change to 1am-9am or if it means I eat lunch during the night. It just seems like we are slowly outgrowing the need for this, as many people work normal hours that used to be considered odd (such as graveyard shifts)
    • The US Government just changed daylight slavings time again, so it's going to start a month earlier and end a month later, so every computer and watch I have that understands this is going to need a patch or to be replaced. I'm sick of those idiots being 'Masters of Space and Time' (Rucker pun), and agree that world wide we should use GMT and if they need to add a second every now and then fine, but forget about all this geopolitical time zone and Daylight Savings time nonsense.

    • Re:Why not adopt a universal ttime? (Score:5, Funny)

      by Anonymous Coward on Thursday November 10, 2005 @07:16PM (#14003045)
      You don't go nearly far enough. Our base 60->60->12 time measuring system is hopelessly baroque and broke. What we need is a sensable metric timekeeping system which takes into account the four-day day as proven by the timecube.
    • Didn't swatch introduce something like that "for people who communicate over the internet" in the '90s?

      Maybe they were too early and now there might be a new audience for that idea?

      (just found a link explaining swatch internet time [csgnetwork.com] and what is swatch internet time [computeruser.com])
    • absolutly nothing.
      Intead of saying, it 8:00 here, what time is it in Hong Kong.
      You would say "We get to work at 1:pm, what time to people in hong kong go to work??"
      thus still doing the same math.

      And if you propose everyone works 8 to 5 GMT, well then what about schools? you seriouslt purpose children get up and go to school during the night? That would realy screw up there natural rythem. Propbably see some interesting psychoatic effects.

      • I would disagree.... The problem with the current system is that numbers get passed around without the frame of reference, with the tacit assumption that it is known. So, when I say it's "5pm", it's like saying, "the temperature is 13" or "the wind speed is 49". 49 what? Using a timezone suffix (3pm PST) provides the necessary and sufficient information, but still requires extra knowledge to do the math -- what is the time difference between PST and where I'm at right now? It doesn't help that daylight ti
      • Intead of saying, it 8:00 here, what time is it in Hong Kong.
        You would say "We get to work at 1:pm, what time to people in hong kong go to work??"
        thus still doing the same math.

        Exactly, so for purposes of working out whether it's a reasonable time to call someone around the other side of the world, things would be exactly the same. No better and NO WORSE.

        But for other purposes we would get major advantages. If I tell you that I plan to call you at 8:00 am tomorrow then you only have to worry about whether t

      • Re:Becasue that would change (Score:5, Insightful)

        by AK Marc ( 707885 ) on Thursday November 10, 2005 @08:06PM (#14003499)
        You would say "We get to work at 1:pm, what time to people in hong kong go to work??" thus still doing the same math.

        This seems like something that only people that don't play internationally think is a problem. It doesn't matter when they get to work. If the meeting is at 84:25 Global Time, then they will either be there, or they will request a time change. I couldn't care less if I schedule something at high-sun where I am and it is dawn, dusk, or some other time elsewhere. If they aren't going to be in the office, they suggest an alternate time.

        This is much simpler than the current system. Ever have a conference call with people in 4 or more timezones? "We'll get back on tomorrow at 4." "Wait, is that East, Mountain, Hawaii, Alaska, or Pacific?" "Um, how about your time?" "Who said that, are they in East Coast time?" "No, Mountain." "Ok, so that's 4 p.m. Mountain tomorrow" "Wait, that's like 6 p.m. East, can we move it up a little?" and so on and so on. Then, when you finally get off the call, you have to do the math yourself anyway to figure out the local time and mark you calendar.

        Yes, I have done business internationally, and I deal with people outside my time zone more than within my time zone. It would be much easier to have everyone work of Zulu time or somesuch. But, it doesn't matter if that's what I'd prefer, for if everyone else doesn't know what Zulu time is, they can't use it. But the simple fact is that it would have greatly reduced my math, not increased it or kept it the same.
    • Because then lots of school kids would have to walk to school in the dark. I'm the last one to scream "think of the children!!1!one!", but that's a dumb idea on its own.

      Besides, why force so many people to spend a lot of their time living at night? Sure, *I'd* actually quite like it, but then I'm weird like that. Would you really force people to emigrate just to be able to live in the light?

    • Better yet, divide the week into six days of 28 hours [dbeat.com] and get more leisure time.

    • Was:
      "Mum, you realise it's 3am in the morning here?"
      Now:
      "Mum, it's sleepy time here."
    • What problem would that solve exactly?

    • Why not just forget about time zones, day light savings and create a new universal global time. So what if it makes my 8am-5pm job change to 1am-9am or if it means I eat lunch during the night. It just seems like we are slowly outgrowing the need for this, as many people work normal hours that used to be considered odd (such as graveyard shifts)

      Well, you have to admit that having a local time is convenient. It would be a real bitch if for every different part of the world you had a different time for "noon"

    • First off, we already have a universal time. It's called GMT (or UTC or Zulu or whatever you may call it) and you are welcome to set your clocks to it, refer to it sleep by it, wake by it, eat by it, and tell all your friends about it.

      Secondly, local time is a reference to what part of the day it is in a ceartain part of the world. You always know that if someone tells you it's midnight that it is dark outside for them and they are likely staying up late and if someone tells you it's 9:00 AM it probably m
  • On either side of the issue. The article wasn't exactly informative, but it would seem to me that most people don't care, and those that do have an emotional investment in the problem.

    The article *did* highlight some reasons why the clock should be kept the way it is ( and for the record, I'm all for leaving shit alone when it's working ), but the reasoning wasn't sound. They were saying they need to know the exact time measurements were taken on the other side of the world. Why wouldn't you have that wi

  • WOW (Score:3, Funny)

    by Anonymous Coward on Thursday November 10, 2005 @07:09PM (#14002975)
    A WHOLE EXTRA SECOND EVERY 18 MONTHS, I can do SO much in a second, like, wow, get about 2 extra keystrokes in to a Slashdot comment! This is so exciting, but seriously, this is news? Am I just crazy or does this have a significant importance on my M$ bashing life?
    • Wow, you type slowly... I think most slashdotters can type upwards of 60WPM, which is much more than a couple letters a second ;)
  • next year, I'm all for it!

    Dave
  • Is it just me or is the fact that they waited until four paragraphs from the end of the entire article to actually state what the change proposal was? They have this massive amount of build up and talk to discord, but I read most of the article wondering, "err, I wish I knew what the proposal was so I can put this whole thing in context".

    • Re:Oddly written article (Score:5, Insightful)

      by grasshoppa ( 657393 ) on Thursday November 10, 2005 @07:21PM (#14003095) Homepage
      They were "spinning". By the time you got to the actual proposal, you already had a tainted opinion of it, only to have them tell you that the scientists in question don't want to comment about it.

      It was a rather heavy handed approach to it, I might add.
    • I'm sure its just you dude.
      I can't imagine two separate people actually Reading TFA.

      But honestly, I'd be supprised if a proposal like this wasn't horribly convoluted to read.
    • Righto. Most of the article is trying to stir up indignation about time ever-so-slowly migrating away from Greenwich, England. Why would that be wanted? Because leap seconds are a pain in the arse.
    • This was horribly written article. Even after reading the whole thing I'm not entirely sure what the proposal is. Although from what I can tell, the submitter got it backwards. The US scientists want to get rid of the leap seconds, not add new ones.

      I personally don't see why there is a need to change any of the existing standards - especially the one used by everyday people. The best thing about standards, is that there are so many to choose from. If there was ever a feild where that statement was true, it
    • Is it just me or is the fact that they waited until four paragraphs from the end of the entire article to actually state what the change proposal was?

      It was worse than that - they wait four paragraphs to tell you that they don't know what the proposal is because they couldn't get anyone making the proposal to take the time to explain it. That has to be one of the worst articles I've read in a wile - basically "UK time keepers are upset because some US group is making some proposal to change how time is ke

  • Pretty dumb summary (Score:5, Informative)

    by Danuvius ( 704536 ) on Thursday November 10, 2005 @07:12PM (#14003000)
    The BBC reported yesterday that U.S. scientists want to change the current system which keeps clocks in sync with solar time by adding a leap second every 18 months or so. This has rattled a few cages with the scientists and operators involved in GMT-related projects and facilities as it would effectively remove the importance of the meridian from timing.
    Pretty dumb summary...

    What the US scientists are suggesting is that we ignore the earth's rotation in our time-keeping, and just try to keep roughly in synch by arbitrarily adding leap-seconds (as opposed to adding them based on our actual observation of the slowing of the earth's rotation). i.e.: Noon will be when your shiny digital watch says it is, not when the sun is precisely above the prime meridian (or precisely X.X hours plus or minus from said event, depending on your timezone).

    Dumb, dumb summary... the UK is defending the idea that humans (of both the blow-joe and the astronomical sort) base their sense of time on the earth's rotation... and so our method of time-keeping should do so as well.

    God... what a dumb summary...

  • Similar... (Score:2, Informative)

    by CupBeEmpty ( 720791 )
    This seems in the same vein as the ICANN/Root Servers debate. Who controls things like this in an ever more connected world. My view is if it isn't broken why mess with it?

    From the article it seems like the leap second is annoying but the leap hour is too much and not frequent enough. If it really that much trouble to keep resetting high precision clocks then why not compromise at leap 10 seconds or some other standard.

  • It's all software (Score:3, Interesting)

    by G4from128k ( 686170 ) on Thursday November 10, 2005 @07:15PM (#14003038)
    Is there really a difference between adding a second to the clock or subtracting a second in the software that uses the clock? Anyone who wants to convert an accurate clock signal (in whatever time-base) into an accurate physical parameter (e.g., the Earth's physical or angular location in space) is going to use software. Diddling a constant in the code or in a set-up file would just as easily change from solar time or earth time or whatever time-base one wants to use.

    The only semi-compelling argument that I can think of is that solar time might be more stable -- the rate of change of the Earth's rotation rate isn't a constant (varies during the year and solar cycle) so the Earth-time leap second process occurs with some irregularity.

    • The problem is that you don't know in advance when http://hpiers.obspm.fr/ [obspm.fr]International Earth Rotation Service (IERS) is going to introduce another leap second. They monitor Earht roration and could do it with only 6 month notice. The latest leap second was anounced this summer and we had to spend few weeks to add it to our data files and test the app before the release. If we had a release a month earlier we would not have included it and it would result in a small, but unacceptable errors unless users up

      • Re:It's all software (Score:5, Informative)

        by stienman ( 51024 ) <adavis&ubasics,com> on Thursday November 10, 2005 @09:57PM (#14004188) Homepage Journal
        It basically means that there is no way to build an embedded software and leave it running disconnected from anything and maintain high time accuracy at the same time.

        1 second is 18 months is 21 parts per billion.

        If your clock needs to drift less than one second in 18 months, then you're already using an atomic clock or primary or secondary time source. This means that you are also going to go to the trouble of synchronizing your clock with some external standard that is, eventually, a primary clock.

        If you can't get the leap second information from your primary time source, then it doesn't matter if you lose 1 second over 18 months - unless you have an atomic clock on board you're going to drift that much in shorter than 18 months. If you have a cheap atomic clock you may still drift that much.

        -Adam

      • Re:It's all software (Score:5, Insightful)

        by tricorn ( 199664 ) <sep@shout.net> on Thursday November 10, 2005 @10:15PM (#14004290) Journal

        You can't maintain a highly accurate clock without external synchronization. Why doesn't your external synchronization source include leap-second information (including when the next one is going to occur, as soon as it is known)? It's no more error prone than having the clock data itself be wrong.

        The application itself should be tested against leap-seconds, there's no reason you should have to test to see if a particular leap-second is going to cause a problem (just as you don't have to test it for each time the clock rolls over from 23:59:59 to 00:00:00). You add ONE LINE to a leap-second file, if you did it right, or just let NTP do it for you if you did it even more correctly.

        Note that the NTP epoch implementation is itself arguably done incorrectly. A reasonable kernel can handle it better by having the NTP daemon update a leap-second file, keep a fixed Unix epoch and correct to UTC in the libraries while keeping a constantly running clock going.

  • UTC - is universal time (Score:5, Informative)

    by linuxbert ( 78156 ) on Thursday November 10, 2005 @07:17PM (#14003061) Homepage Journal
    UTC or coordinated universal time (UTC is the acronym that was agreed on because the british and the french had a disagremment about the word order)is the standard time for the world. a time zone is 15 degress of longitude, and is equal to 1 hour. thus if you know the local time, and have a 0 point (Grenwich meridian) and can do some math, you know where on the planet you are.

    UTC was agreed upon by an international body, many many years ago. it is now frowned upon to call it gmt (though pretty much everyone does)Not everyone follows it, and their are many variations (Newfoundland time - 30 minutes off)
    some countries still have their own meridians.

    time is tied to geography.

     
    • No... perceived time (more accurately measured astronomical time) is tied to geography.

      In 1967 a second was defined precisely as the duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom. This gives us a precisely defined absolute time.

      This was a pretty close match to the original second which was defined, imprecisely as a fraction of the tropical year so the precisely defined absolute time pretty

  • John Flamsteed (Score:5, Funny)

    by kst ( 168867 ) on Thursday November 10, 2005 @07:23PM (#14003113)
    From the article:
    The decision stemmed from the work 200 years previously of the first English Astronomer Royal, John Flamsteed, who calculated that the Earth rotated on its axis once every 24 hours.
    So he was the first person to notice this? How lucky for him that an hour already just happened to be 1/24 of a day!
  • We want to avoid sunrise at noon? At the current rate, that will be in about 32000 years. I think sometime between now and then we could do a somewhat larger shift.
    In the mean time (pun intended), I seem to recall from other stories that the US proposal was to stop having a leap second every year and a half or so and have something like a leap minute every century.

    As far as precision measurements go: How does adding a second to your clock in the middle of a precision measurement help the supposed measu

  • It'd be much better to add TWO leap seconds every 36 months (that is 3 years). Or (insert some fractional number here) every 4 years, so that it gets done along with the leap year period.

    You don't really expect users to start adding seconds to their digital clocks every N months, do you?

  • Simply (Score:3, Insightful)

    by hurfy ( 735314 ) on Thursday November 10, 2005 @07:27PM (#14003146)
    Tell me how to make a withdrawal from Daylight Savings and they can have a few seconds from me and put them whereever they like ;)

    I'll worry about it when my $2000 computer comes close to keeping time as good as my $2 watch :(
    • If you're running Windows, try Dimension 4 [thinkman.com].

      If you're running something Unix-like, you should be able to set up an ntp daemon.

      But I've always wondered why devices that run off 60-Hz line current (in the US, anyway) have trouble keeping their clocks accurate. Sure, that doesn't help if the machine is unplugged, but it should be more than accurate enough whenever it's plugged in. (The utilities go to a lot of effort to keep 60-Hz AC in sync; why not use it?)

  • We don't add in "leap" seconds into our clocks at home.
    Yes we do. There will be one this year. The hourly 'pips' on BBC radio will get an extra pip at 2006-01-01 00:00:00.
    --

    You can listen to this on WWV/WWVH on 2.5, 5, 10, 15, and 20MHz
  • to allow yourself to get to the stage where you're a whole hour out of synchronisation with the Sun seems to be mad.

    And yet we do so 6 months out of the year, and starting in 2007 we'll do it for even longer.

    Seriously, though, at least when we switch to daylight saving time (or summer time as they call it across the pond) the offset is easy to account for.
  • I am writing this from Exeter in the south west UK, 300 yards away from me is Exeter St Davids railway station, which links us to Falmouth in the west, and London in the East.

    Before this railway line was built (by I K Brunel, to link the deep water port of falmouth to london so his passengers could get his trains between london and cornwall and then his ships between cornwall and the USA, which saved ship travel time up the english channel, around the corner and then up the thames) we here in Exeter had our
  • Basically, the UK (and others?) want to keep 12 noon as when the sun is at it's highest point above Greenwich (pronounced Grenidge for our Atlanticly challenged), and change the clocks accordingly to keep them in sync, but the US want to let time gradually go out of sync from the Earth's physical position, so that at some point, way, way into the future, 00:00 might be when the Sun was highest in the sky over Greenwich. Which seems really silly to me.

  • Everything about leap seconds (Score:4, Informative)

    by at10u8 ( 179705 ) on Thursday November 10, 2005 @07:48PM (#14003315)
    For a pretty full understanding of what is happening, what has happened, and why, see history of the effort [ucolick.org], implications of change [ucolick.org], definition of terms [ucolick.org]
  • ...because the story just refers to "the Americans" or "the American delegation" or "US scientist"....

    kinda blanket accusation, don't you think?
  • There are two flavors of time - TAI (Temps Atomique International or somesuch, I believe), which is measured by the decay of cesium atoms. There is also UTC (Universal Coordinated Time) which is measured by the rotation of the earth.

    Naturally, there is drift - this is where the leap seconds come from. Right now, UTC time is 22 seconds behind TAI time. What they are proposing, it seems, is eliminating UTC. I see absolutely no good or sound reason to do this, given that precision timekeeping insturments alrea

  • The Earth is slowing down? (Score:3, Interesting)

    by Bit_Squeezer ( 824571 ) on Thursday November 10, 2005 @07:54PM (#14003382)
    Why dont we all take out our photon drives (laser pointer) point em westerly and fix the real problem?
  • I want to move the freakin' Meridian to the US. Maybe NYC, or maybe somewhere closer to the middle of the country, like Dallas. What's so special about Greenwich? Hell, move it to NYC and make it GVMT.
  • I definitely don't understand why the Americans would propose dumping UTC. After all, leap seconds are for the convenience of the public.
    If they are so interested in avoiding leap seconds, why don't they just use TAI [navy.mil] and let the others keep using UTC?
  • This proposal will make my life a living hell. Unless, the leap seconds were added on a strict schedule that was known well in advance. And even with that, I'll still have to change a butt-load of code to accomidate it.

  • Messing up the time systems (Score:3, Informative)

    by janwedekind ( 778872 ) on Thursday November 10, 2005 @08:10PM (#14003535) Homepage
    Ever since the beginning of measurement of time the main goal was to keep time in sync with the rotation of the earth and the date with the orbiting around the sun as accurately as possible. Otherwise a date wouldn't tell the season and the time of day wouldn't tell about the sun's position.

    Programmers of astronomical software already have trouble enough:

    1. The year -1 is followed by the year 1
    2. 4.10.1582 is followed by 15.10.1582, because only then the length of a year was measured with sufficient accuracy. The new system of leap years will only need a fix of one day in another thousand years.
    3. Last century Ephemeridical Time (ET) was introduced to serve as a constant measure of time (in contrast to the Universal Time (UT)). The commonly used time is UTC, which is running with the same "speed" as ET and being corrected every once in a while, when (UTC-UT) becomes greater than 0.9 seconds. Astronomical software has to know UT as well as the difference ET-UT: The positions of other planets have to be computed with ET and the rotational angle of the earth with UT.
    ET-UT is more than 60 seconds at the moment already. Replacing UT/UTC with ET-60 s will not really make things easier and it will deprieve the old system of its benefits! If someone needs a ET-clock for doing satellite navigation, he shouldn't force everyone else to do so as well. If the U.S. scientists keep pushing, I'll switch to a russian time-server in the future.
  • we need Super Duper Double-Duty (tm) Daylight Saving Time. For every day of the year, turn the clock forward one hour at 3pm (since nothing gets done at work after 3pm anyway), and then turn the clock back one hour at 3am (since studies have shown that a significant percentage of Americans are sleep-deprived and thus the extra hour of sleep would give an instant boost to productivity!)

  • It's the algorithm, stupid. (Score:5, Informative)

    by anon mouse-cow-aard ( 443646 ) on Thursday November 10, 2005 @09:12PM (#14003952) Journal
    BBC article completely misses the point. The international time reference, since the 1950's, has been UTC, and used tuned according
    to atomic clocks, not the earth's rotation. There are time references used specifically for astronomy, such as sidereal time, solar time, etc... (http://en.wikipedia.org/wiki/Sidereal_time [wikipedia.org]) There is absolutely no reason why astronomical time references have to match precisely to the time reference used by normal people.

    The problem is that, today, there is no algorithm for knowing when to insert leap seconds ahead of time, which means you cannot calculate any time accurate to the second which is more than 18 months in the future, because you have no idea whether or not they will decide to insert a leap second. Nor is there any algorithm, other than a table of the known values to determine when to insert leap seconds. Add that they used to add them in June in some years, and December in others, and sometimes had two in the same year, and you get a feel for how chaotic it is.

    Accumulate these differences over twenty years, and you have a serious problem. That is why the global positioning system uses it's own time reference, which has no leap seconds. When you're calculating position based on propagation delays, leap seconds are a mess. so GPS time is currently (http://tycho.usno.navy.mil/gpstt.html [navy.mil]) fourteen or fifteen seconds different from UTC. (how many leap seconds since 1999? no way to calculate, you just have to know.) Seconds are the basis for all computer based time scales. These little nudges make very little sense. It would be far smarter to insert a leap minute, every... oh... 90 years. Or make the leap second insertion an algorithmic event, and not some random decision negotiated among a committee of astronomers.

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