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United States Upgrades

U.S. Moves to Kill Leap Seconds 601

Posted by CowboyNeal from the time-to-kill dept.
blacklite001 writes "Not content with merely extending Daylight Savings Time, the U.S. government now also proposes to eliminate leap seconds, according to a Wall Street Journal story. Their proposal, 'made secretly to a United Nations body,' includes adding 'a "leap hour" every 500 to 600 years.' Hey, anyone remember the last bunch of people to mess with the calendar?"
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U.S. Moves to Kill Leap Seconds More

U.S. Moves to Kill Leap Seconds

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  • now correct me if im wrong (Score:5, Insightful)

    by thegoogler ( 792786 ) on Saturday July 30, 2005 @09:55AM (#13201741)
    but it seems to be working perfectly fine as it is, why fuck with it?

    • Apparently not... (Score:5, Informative)

      by interactive_civilian ( 205158 ) <mamoru&gmail,com> on Saturday July 30, 2005 @10:06AM (#13201788) Homepage Journal
      According to TFA, it isn't working perfectly fine:
      But adding these ad hoc "leap seconds" -- the last one was tacked on in 1998 -- can be a big hassle for computers operating with software programs that never allowed for a 61-second minute, leading to glitches when the extra second passes. "It's a huge deal," said John Yuzdepski, an executive at Symmetricom Inc., of San Jose, Calif., which makes ultraprecise clocks for telecommunications, space and military use.

      On Jan. 1, 1996, the addition of a leap second made computers at Associated Press Radio crash and start broadcasting the wrong taped programs. In 1997, the Russian global positioning system, known as Glonass, was broken for 20 hours after a transmission to the country's satellites to add a leap second went awry. And in 2003, a leap-second bug made GPS receivers from Motorola Inc. briefly show customers the time as half past 62 o'clock.

      "A lot of people encounter problems with their software going over a leap second," said Dennis D. McCarthy, who drafted the U.S. leap-second proposal while serving as the Navy's "Director of Time."

      Now, I can't say that I completely understand why resetting a clock should be so complicated, but it seems to cause problems...
      • You do not even have to add seconds, just stretch the last few seconds on those computers. That is done all the time by programs as ntp, and it affects nobody. That in reality there has been a leap second, and the real clock has a slight programming problem, is not a big deal to anybody. That clock is an independent object which does not control any other real objects (except ntp, which will just ignore second 61 as an error, and wait for a correct time to come by, which will come a few seconds later).

        The
      • In addition to the weirdness of having second 60 in a minute, you get that added headache that leap seconds are non-deterministic... you can't predict ahead of time when they will happen. Imagine you make a very precise schedule in advance (e.g. scheduled events on a spacecraft) and then a leap second is announced and everything is then off by a second. Now you have all of these tables out there that are wrong that you have to find and then correct... a major headache when your working with something whe

        • Re:Die - leap seconds - Die! (Score:5, Insightful)

          by Anonymous Luddite ( 808273 ) on Saturday July 30, 2005 @10:45AM (#13201991)
          >> you can't predict ahead of time when they will happen.

          WHy would you need to guess when? surely the seconds are added at arbitrary points as required, but I can't imagine it is done with no warning.

          >> Imagine you make a very precise schedule in advance (e.g. scheduled events on a spacecraft) and then a leap second is announced and everything is then off by a second.

          The industry I working does use highly complex systems where precise timing is critical. I can tell you from experience that you have to design for timing errors. They happen, not if but when.

          Besides, assuming you've got a system that requires real-time function and accuracy to the second, why would you sync to outside time for anything but maintenance? Keep your timings relative to the system itself. Then you just need to worry about internal clocks...

      • Re:Apparently not... (Score:5, Insightful)

        by jayhawk88 ( 160512 ) <jayhawk88@gmail.com> on Saturday July 30, 2005 @10:41AM (#13201966)
        So instead of letting private companies eventually wise up and write their software to take into account/be able to deal with leap seconds, let's fuck with the entire way we measure time on a global scale. Way to go government.

      • Re:Apparently not... (Score:5, Interesting)

        by Entrope ( 68843 ) on Saturday July 30, 2005 @10:41AM (#13201970) Homepage
        Resetting the clock is not complicated, but the current system means there is a 61st second in a minute, as your quote of TFA mentions. People -- including software developers -- are strongly used to dealing with 60-second minutes, and software sometimes makes that assumption. It just requires attention (sometimes a lot of attention) and extra code (sometimes a lot of extra code) to get it right, but since very few people pay attention when a leap second happens, bugs are easily overlooked.

        Since leap seconds are based on changes in the time period of Earth's rotation (the sidereal day), and the decay is both very slow and influenced by hard-to-predict factors, leap seconds are not reliably predictable. They can only be announced when they are necessary -- and so it is easy for the displayed time to drift if a leap second announcement is missed or ignored.

        Leap hours, though, are different beasts. Virtually every piece of software in the world that displays time knows how to deal with the hour jumping forward or backward. That transition happens predictably and affects a huge number of users, so errors are easily noted.

        • Re:Apparently not... (Score:5, Insightful)

          by tricorn ( 199664 ) <sep@shout.net> on Saturday July 30, 2005 @11:06AM (#13202087) Journal

          But the hour WON'T "jump forward or backward an hour". You'll either have a 23-hour or 25-hour day, plus it will only happen once every 500 years or so. When are you going to test it? When are you going to start putting it into programs? And you thought that programmers storing only 2 digits for the year were stupid and shortsighted...

          The whole thing is a crock. Software that hardcodes in conversions between days/hours/minutes/seconds, AND needs to be so accurate to the rest of the world that it has to account for leap seconds, must be rewritten to use a standard library routine. Internally, it should simply keep a seconds counter, and base all intervals off of that. There's no excuse for doing it wrong, and code that does do it wrong should be rewritten if it is critical.

          • Re:Apparently not... (Score:4, Informative)

            by 42forty-two42 ( 532340 ) <bdonlan.gmail@com> on Saturday July 30, 2005 @01:55PM (#13202872) Homepage Journal
            It does, actually. At least in unix-like systems, time is represented by the number of seconds since January 1, 1970 (known as the Unix Epoch). There are C library functions to convert it to a date, accounting for time zone, locale, formatting, etc.

      • Network Time? (Score:5, Insightful)

        by BobPaul ( 710574 ) * on Saturday July 30, 2005 @11:56AM (#13202294) Journal
        From article:
        But adding these ad hoc "leap seconds" -- the last one was tacked on in 1998 -- can be a big hassle for computers operating with software programs that never allowed for a 61-second minute, leading to glitches when the extra second passes.

        Why would anyone need to set a 61-second minute to account for leap time other than the guys at NIST in charge of the official time? Just set all your computerized clocks to network sync. We have a network time server that re-syncs itself ever hour and then everything else checks that occasionaly. I've never had to do anything about a leap second except maybe be off by a second for a few hours until time resets itself...

        That 0.01% of businesses that require absolute perfect time need to hire better software programmers rather than fscking with how we define time.

        "OMGZ! Motorolla screwed up in 2003, and some Russians did the same in 1997! Let's pass a law to protect them!!!"
        --
        Don't fight Firefox! Let FireFox fight YOU! [bobpaul.org]

      • Re:Apparently not... (Score:4, Informative)

        by cnettel ( 836611 ) on Saturday July 30, 2005 @12:37PM (#13202487)
        Remember that a lot of systems use "seconds since certain point in time" (like January 1, 1970, GMT, you UNIX-based bastards). There are functions in the C runtime library to convert from those to normal calendar dates. I find it kind of unsatisfactory that you'll have to add in magic numbers for each of the leap seconds as they are added. Of course, having a leap hour for some coders in a few centuries won't be too nice, but they will probably be able to declare that it's coming several years in advance, or ditch it altogether. One way or another, I would like to keep the calendar definition and conversion between different types simple. Avoiding leap seconds is one tiny step along that road.
    • The problem is that it isn't working fine. To begin with we should have 13 months in the year, not 12. Months are supposed to reflect lunar cycles and there are 13 of them a year. The year is one day and some change longer than 13 (28 day) months a year. Ever noticed how the business world works off 13 periods a year? and of course the menstrual cycles too. Take a look at this [wikipedia.org] sometimes.

      • Re:now correct me if im wrong (Score:5, Interesting)

        by gstoddart ( 321705 ) on Saturday July 30, 2005 @11:38AM (#13202222) Homepage
        The problem is that it isn't working fine. To begin with we should have 13 months in the year, not 12. Months are supposed to reflect lunar cycles and there are 13 of them a year.

        Actually, the 12 months was to align with the constellations of the zodiac so that certain constellations will be in the same place at the same time. It keeps astronomical calendars in tune.

        Cultures which slavishly kept to a lunar calendar (another method of timekeeping, but it ignores the fact that we revolve around the sun) found that every bunch of years their months would be in the wrong season.

        A month is an abstraction made by humans for timekeeping, there is no 'should have 13 months' that closely aligns with actual astronomical time passage, which is far more important.

        Keeping track of solstices and equinoxes are really important when it comes to things like knowing when your seasons are changing.

  • Unfair to clockophiles! (Score:3, Funny)

    by shobadobs ( 264600 ) on Saturday July 30, 2005 @09:55AM (#13201743)
    http://leapsecond.com/ [leapsecond.com] -- This guy should complain. They're taking all the fun out of his clock collection!
  • I say the government should move to Internet time and leave the big boy alone. Looks like that already does what it wants...

  • snore... (Score:2, Redundant)

    by ewe2 ( 47163 )
    like this actually helps to fix an already-broken calendar. There are many alternatives but legislators like to pull these stupid stunts to avoid actual real decisions.

  • Leap Minute (Score:2, Insightful)

    by GeekWade ( 623925 )
    Wouldn't a leap minute every couple of generations be better than being close to an hour off base for a hundred years or so?
    • Not a problem. We presently work up to a full day off base every 4 years.

      What problems do you expect from being up to an hour off base if everyone is off the same amount?
      • Not a problem. We presently work up to a full day off base every 4 years. What problems do you expect from being up to an hour off base if everyone is off the same amount?

        The two aren't the same thing. The "leap year" thing is to adjust for the earth's orbit around the sun. Leap seconds adjust for the earth's rotation. Waiting until we are an hour off to realign with the earth's actual rotation would be like waiting till we were a full month off to adjust for the solar orbit.

  • Just to say that, TFA to the contrary, Greenwich Mean Time was scrapped years ago as being too expensive to maintain the equipment.

    So while there may be plenty of brits that think this is a silly idea (me included) it's got bog all to do with GMT.

    HTH

  • Sometimes, with our very limited 80 year lifespans, we start to think that everything that we do now is the absolutely most important thing ever, and we make decisions based on that rather than looking to history for a sense of scale. 500 years ago, people weren't reading, they weren't really doing much of anything productive. It wasn't until the Renaissance that things really started humming.

    So 500 years from now, with a whole hour of time slip, what will they think of how we just decided to change the manner in which we adjust time?

    In China, there is only one timezone, but it works terribly since half the country wakes up in the dark and the other half wakes up in bright sunlight. They have adapted to this by "unofficially" setting work hours according to the longitudinal timezone rather than the government-mandated timezone. I wonder if there were a huge leap second buildup whether people would just start waking up according to the absolute time rather than the political time.

    I think it's a bad idea, and I can't think of the benefits. But I guess I'm not a scientist, so I wouldn't understand those issues.
    • In China, there is only one timezone, but it works terribly since half the country wakes up in the dark and the other half wakes up in bright sunlight. They have adapted to this by "unofficially" setting work hours according to the longitudinal timezone rather than the government-mandated timezone.

      My feeling is that they should simply have a chronometer which keeps ISO standard time. Go ahead and use an hours-minutes-seconds based system so that people get used to it. Forget leap-seconds - no need for tha

      • Re:Can we say what we will think 500 years from no (Score:5, Insightful)

        by PhYrE2k2 ( 806396 ) on Saturday July 30, 2005 @11:38AM (#13202221)
        Forget time zones - no need for that either

        I can see it now... the day will shift mid-day. Try programming that one! The 23rd of August (for example) will change over in the MIDDLE OF A WORKDAY! Not only that, it'll change over at a different time in the work day (so sun's position, but in your proposal not physical time) for every region.

        The whole point of time zones is to keep time reasonably standard no matter where you are. I can travel half way across the world and I still wake up at 8am, eat lunch at noon, dinner at 7pm, etc. The concept of a day is very engrained in us. Today is a Saturday! Imagine if it was also sunday based on my location.

        Besides- the US would want to manage it, so they'd end up with the same time scheme they have now (probably picking up EST or Mountain as their base zone), while the rest of the world rolls over laughing at their proposal.

        -M
        • I wake up and eat breakfast in the morning (after the sun comes up).

          I eat lunch at mid-day (when the sun is roughly over head).

          I eat dinner in the evening (usually when the sun is starting to descend).

          I go to sleep at night (after dark.)

          Does it really matter if I wake up at 0000 isntead of 0800? Does dinner taste differently at 1900 than it does at 1100?

          Curious.

      • But what would you put into your crontab? You don't want to run your backup-which-slows- the-system-considerably to occur in the middle of the workday, so you would probably set it to some relative time, like "sunrise - 5 hours".

        And if techies couldn't cope with it, what about normal people. They would start almost instantly to use a relative time (or keep to the old time, government be damned). So it would only diminish the usefulness of "official time" and lead to more chaos.

        - Erwin

      • Re:Can we say what we will think 500 years from no (Score:5, Insightful)

        by Guppy06 ( 410832 ) on Saturday July 30, 2005 @01:13PM (#13202660)
        First off, you just missed the entire freaking point of the paragraph you cut and pasted. In the absence of Beijing allowing people to live in separate time zones (ala Russia, Canada, US, etc), the people have chosen to implement their own time zones because that's what they want. A global standard for time like this has little purpose when people rarely cross integer numbers of degrees of longitude throughout the course of the day and would rather have a local, sun-based standard that attempts to divide the day into parts based not on where the sun is in the UK, but where the sun is where you're standing right now.

        We're diurnal creatures and we liking having a time standard that takes that into account. You can't wish away biology with some global standard.

        "My feeling is that they should simply have a chronometer which keeps ISO standard time. "

        You misspelled BIPM.

        "An office would set their working hours as 1830-0230 and that would be it. No changing the time in the summer/winter/etc. They could change their hours in the summer/winter though."

        So, instead of just having to deal with jet lag when I cross multiple degrees of longitude in a short amount of time, I also have to cope with the fact that the operating hours of businesses I've grown accustomed to where I live have absoluntely no meaning here. Instead of today's world where, upon arriving, I simply press a few buttons on my watch, I now have to constantly apply a mathematical operation to what my watch says ("If I'm used to somethign happening at time X at home, then it must happen at X-Y here..."), that all but elminates the purpose of having a timepiece to begin with. I want to know what part of the day it is for the people around me, the people I have to interract with, and if a timepiece can't do that (indeed, begisn to serve as an obstacle to it), it's lost its purpose. I would literally be better off looking at the position of the sun in the sky, thereby eliminating several centuries of progress.

        And where you suggest that businesses change their hours instead of simply changing the frame of reference (which is what DST represents), you're advocating a system that would bree chaos. Changing the frame of reference, by definition, is uniform. Every business continues to be adequately synchronized with the other businesses they must deal with in the course of the day. If everybody has to change their own hours, then all you'd do is introduce confusion until everybody agreed on a regular, synchronized change of hours outside of the so-called standard you're proposing (making the standard useless). And even then it would be less efficient than simply changing the clocks.

        Have you ever had a physics class? If a problem is set in an ugly change of reference, would you rather constantly have to apply a long list of ugly transforms, or would you rather save yourself a lot of time and effort and simply change the frame of reference?

        "An office on the other side of the country might start work at 1700 instead."

        Your system also complicates communications across long distances. Time zones simplifies differences in time between two locations into an integer number of hours, allowing a simple calculation to be done after glancing at a clock set in the local frame of reference. Without time zones, everybody would attempt to set their operating times accoridng to time at the local meridian (again, going back to local solar time and making mechanical time standards worthless), and you'd be lucky if the difference between your times and theirs was an integer number of minutes. Intercontinental communications would require a degree of pre-arrangement (to first learn their hours of operation) to make sure that when you attempt to call them, they're there to answer the phone. On the other hand, today I know that businesses across the country (if not across the world) tend to stick with a "nine to five" work day, and all I would need to know is what state or country my

    • Re:Can we say what we will think 500 years from no (Score:5, Funny)

      by ltbarcly ( 398259 ) on Saturday July 30, 2005 @12:58PM (#13202587)
      500 years ago, people weren't reading, they weren't really doing much of anything productive.

      Except growing food, raising livestock, getting married, raising children, defending themselves, scheming, talking with neighbors, and saying, "Someday Martha, one of our great great great great great ... great grandchildren will grow up to post something stupid on something called the Internet."

      I wonder if there were a huge leap second buildup whether people would just start waking up according to the absolute time rather than the political time.

      Time is an arbitrary concept created by man. People get up according to when they have to be at work, and if that isn't sometime in the morning they get up when it is convenient for them. Some people have to be at work at 8, others at 9, some at 6 or 7. Where does politics come into this? All the government does is produce a standard benchmark time so we can communicate about time, and know that we will be understood.

      Jesus saved me from my past. He can save you as well.

      Did he really? Unless this is Jesus the Hispanic fireman, I don't buy it. Either a magic supernatural man in the clouds helped you, or you are confused about it. Occham's Razor anyone?

      To illustrate this point, I encourage people to read this: http://www.somethingawful.com/articles.php?a=2800& p=2 [somethingawful.com] (the last post at the bottom). Compare that with what you hear people say about Jesus (the non-fireman one).

  • More info (Score:5, Informative)

    by interiot ( 50685 ) on Saturday July 30, 2005 @10:03AM (#13201772) Homepage
    More info here [ucolick.org], with geeky charts and stuff.
    over the past 30 years (coincidentally since the inception of leap seconds) the rotation of the earth's crust has accelerated. This acceleration is apparently due to changes of fluid circulation in the outer core of the earth. Historical investigations of earth rotation indicate that such accelerations are not unprecedented, and it should not be possible for the acceleration to continue for very many more years.

  • Hmm... (Score:3, Funny)

    by __aaclcg7560 ( 824291 ) on Saturday July 30, 2005 @10:03AM (#13201774)
    I don't see anywhere in the U.S. Constitution that the government has been given authority over time. I guess strict constructionism [wikipedia.org] applies only to judges and not the government. Bummer... There's never a Time Lord [bbc.co.uk] when you need one.

    • Re:Hmm... (Score:5, Informative)

      by TykeClone ( 668449 ) * <TykeClone@gmail.com> on Saturday July 30, 2005 @10:27AM (#13201912) Homepage Journal
      Powers granted to the Congress of the States:

      Section 8, Clause 5: To coin Money, regulate the Value thereof, and of foreign Coin, and fix the Standard of Weights and Measures

      Time is a measure, therefore they actually do thave the authority to regulate it.

      • Just so long as NASA isn't going to use software from anywhere else in the world. They had enough trouble landing on Mars when different groups used metres or feet & inches. If Congress fucks around with time, the next Mars mission will probably hit Mercury...
    • Aside from the fact that it does state that, as the previous poster pointed out, this was just a recommendation to the UN, not a law in itself.

  • neat bit (Score:3, Insightful)

    by putko ( 753330 ) on Saturday July 30, 2005 @10:06AM (#13201790) Homepage Journal
    This bit is neat:

    "The U.S. effort to abolish leap seconds is also firmly opposed by Britain, which would further lose status as the center of time. From 1884 to 1961, the world set its official clocks to Greenwich Mean Time, based on the actual rise and set of the stars as seen from the Royal Observatory in Greenwich, just outside London."

    I had no idea there was still a physical basis for this. I assumed there was a master atomic clock.

    I can see why the USA would do this: they move around the holidays to fit the work week (e.g. Monday or Friday, whichever's closest). Try doing that with Corpus Christi in Continental Europe: it would be considered totally absurd.

    • Re:neat bit (Score:3, Informative)

      by imsabbel ( 611519 )
      yeah, there IS a master atomic clock (or more like a cluster, with each clock weighted differently).
      (also note that this ends 61, about the time atomic clocks became usable)

    • Re:neat bit (Score:3, Insightful)

      by Dun Malg ( 230075 )
      "From 1884 to 1961, the world set its official clocks to Greenwich Mean Time, based on the actual rise and set of the stars as seen from the Royal Observatory in Greenwich, just outside London."

      I had no idea there was still a physical basis for this. I assumed there was a master atomic clock.

      I'm fairly certain there was no atomic clock in 1884. hances are, the atomic clocks arrived on the scene around, oh, 1961 maybe?

    • Holidays are still celebrated on the appointed day; we simply make an observation of them on the nearest work-day if they fall on a weekend because three-day weekends are a happy thing. If you observe the day off for a holiday on a Thursday, how many people are *not* going to try and take Friday off?

  • Planet (Score:5, Funny)

    by dinkster ( 750021 ) on Saturday July 30, 2005 @10:08AM (#13201805)
    I say we adjust the planet's rotation and orbit so we have perfect intervals.

    • Re:Planet (Score:3, Informative)

      by A beautiful mind ( 821714 )
      This whole stuff reminds me of Xerxes [wikipedia.org] who ordered the punishment of the sea because the sea consumed his war fleet. When i mean punishment, i mean "whipping the sea". Makes sense if you're arrogant enough, i suppose.

    • Re:Planet (Score:3, Interesting)

      by hazee ( 728152 )
      Yep, once we get that space elevator working, we'll be able to ship huge amounts of rock up and down, adjusting the angular momentum of the Earth, and thus its spin rate...

      I wonder just how much mass would be required to adjust the length of a day by the required fraction of a second per year?

    • Re:Planet (Score:5, Funny)

      by shawnce ( 146129 ) on Saturday July 30, 2005 @11:23AM (#13202155) Homepage
      I say just blow up the moon, that little bastard is just slowing us down.
  • ...go back to the Imperial system of measures too? Nah, bless you Americans with your lovely paper size known as Letter (and every wierd piece of software that insists on using it).

  • Best quote of the article (Score:5, Insightful)

    by Cybertect ( 85900 ) on Saturday July 30, 2005 @10:12AM (#13201833) Homepage

    The astronomers are not convinced. "If your navigation system causes two planes to crash because of a one-second error, you have worse problems than leap seconds," said Steve Allen, a University of California astronomer who maintains a Web site about leap seconds.

    That's so right.

  • Big leap of faith... (Score:5, Informative)

    by NetSettler ( 460623 ) <kent-slashdot@nhplace.com> on Saturday July 30, 2005 @10:13AM (#13201836) Homepage Journal
    Leap seconds and leap days aren't related. Leap days are related to the need to make a year's length expressible in integral number of days by a sort of infinite series approximation. Unless the length of a year were an actual integral number of days, leap days would be needed even if there was no "slowing" ever. By contrast, leap seconds are added to accomodate "slowing" and are not an artifact of the original relation. The use of the term "leap" for both of these is probably what attracts politicians to "leap" to the rescue. Perhaps they should take a second to reconsider...

    I actually agree that leap seconds are a bit of a mess, and I wouldn't mind seeing a better solution. But the one proposed sounds a bit bizarre. Surely the real problem is an artifact of the infancy of computer systems and the ad hoc, non-general solutions to time representation we've been using due to very small address spaces that are rapidly falling by the wayside. Why not just delay the issuing of them for a couple of decades until we can think harder about the problem. Pretending that any law passed now is going to stand unused for hundreds of years before it has any effect seems a little ... arrogant. I'm pretty sure that, say, somewhere around 2027, we're going to have a lot of discussion about our present representation of time and whether it's the right one...

  • The connected geek question (Score:5, Interesting)

    by astrashe ( 7452 ) on Saturday July 30, 2005 @10:14AM (#13201847) Journal
    The article talks about lots of problems that leap seconds cause with software.

    The problems don't come from the complexity of the underlying problem of adding leap seconds, but rather because leap seconds are added so infrequently that the code to handle the leap seconds isn't well tested.

    So the real question here (to me, at least) is this: what do the leap second problems tell us about how software is developed?

    Are people not thinking about leap seconds when they write code? Or are they thinking about them, but not testing the leap second cases properly? What's going on?

    And how does the emergence of really big collections of APIs affect this? I mean, if people use standard routines for calendar functions, and if people keep their tools up to date, shouldn't these problems be mitigated? Shouldn't we be able to have some hard core calendar geeks solve the problem once in the API, and carry the rest of us?

    If that doesn't work, why not?

    We can solve this particular problem by changing the calendar. But what if we couldn't, and we had to try to address it with engineering practices? How would we proceed?

    • Re:The connected geek question (Score:4, Insightful)

      by fermion ( 181285 ) on Saturday July 30, 2005 @11:56AM (#13202295) Homepage Journal
      I think it tell us that the people we pay to write critical systems are not doing their job properly. This is going to affect very few systems. Most things will check the system clock, and most properly written systems are set up to automatically check some central time server. There are notable exceptions to this, and those exceptions tend to also be poorly written.

      Second, we are talking about a leap second, which happens once every year or so. Not often, but not never. This change is far outweighed by the normal timekeeping error, which for the average watch is like 3 minutes a year. The clock of a computer is not necessarily better. Also, we are only taking about clocks that need to keep track of the time, and not jut the passage of time.

      As such we are really talking about a select set of software that much keep up with the time and not depend on a time server. If good techniques are used, the code to handle the leap second is one place, and good regression testing can check many different scenarios to insure that the code will work and changes do not break it. I am not saying it is trivail, but certain not prohibitively difficult. Since we are talking about network critical devices and specific military hardware, I do not see the problem with funding this development. What is really sounds like is that some people took government money for a project, and now want to changes the specs because they cannot do it.

      The only other thing i can think of is that these apps are 20 years old and no one want to update them. There is some wisdom to letting working system run, but these are obviously not working. Next legislation will the pi=3, and francium will now be known as freedium.

  • Wasn't it Gregor (on the same wikipedia link) who was the last to mess with the calendar? Essentially, they moved back several days because leap days weren't correctly accounted for prior to then.
  • So, it's okay to play with daylight savings time [slashdot.org] but this leap second is a pain and needs to go?
    • So, it's okay to play with daylight savings time but this leap second is a pain and needs to go?

      Right. Two very different problems. The DST issue just involved aribtrary labeling of what time it is. The elapsed time in seconds doesn't change. But when the number of ticks in a minute does have to change, a lot of stuff breaks.
  • From the article:
    In Mr. Allen's view, absolutely not. "Time has basically always really meant what you measure when you put a stick in the ground and look at its shadow," he said.

    I couldn't agree more.

    The only sensible alternative is that we no longer keep time based on celestial mechanics, and we abolish leap days/year, daylight savings and the 365 day year too. Those are annoying to programmers like myself too.

    Let's start counting in Stardates !
  • To use the time-honoured method of finding out government secrets, you read about them in tomorrow's newspaper...
  • Why bother with hour system if we're changing the calendar/time in first place?

    It would make much more sense to use more accurate measuring system like one that bases on half-life of isotopes.

    Of course it would be rather inconvenient to say it's 12*10^6 past last decay of u-358, but it could be commonplace already to our great grandchildren.
    • and apparently I'm coming up with new isotopes too.. that was intended to say u-238, rather than 358..

      oh well, need more coffee

  • Astronomers will be unhappy (Score:5, Insightful)

    by RayBender ( 525745 ) on Saturday July 30, 2005 @10:38AM (#13201952) Homepage
    Doing away with leap seconds has the effect of breaking the connection between the rotation of the Earth and time. The point of a leap second was to compensate for the fact that the Earth changes its rotation rate by very small amounts (due to changes in mass distribution).

    It will make it harder to run telescopes, but also a number of navigational devices. The mention of the Glonass screwup is actually misleading - even if you abolish the leap second, you still have to have software in your satellites compensate for changes in Earth rotation rates - abolishing the leap second will not change that at all.

    Probably the worst argument for getting rid of leap seconds is "they are rare anomalous events that cause potential danger for systems like ATC that are tightly coupled to time". That's misleading, though, because the proposal is actually to replace leap seconds with leap hours every 500 years. Which means that you replace a small, bi-annual anomaly with a gigantic one 500 years from now (on a scale larger than the Y2K bug, for sure.) Kicking the problem down the road so to speak - I'm not surprised it was originally suggested by a bunch of lazy programmers. Not to mention that that practice would mean that 400 years from now solar noon would be almost an hour away from actual noon (not that big a deal, of course, but annoying).

    The argment for keeping the leap second is more than just tradition - it has practical value too.

    • Blockquoth the poster:

      Not to mention that that practice would mean that 400 years from now solar noon would be almost an hour away from actual noon

      Well, solar noon is up to half an hour away from calendar noon now, for places near the edges of timezones. Somehow life goes on.
  • Would be the French. Metric weeks and all that.

    Haha.

  • Last bunch of people? (Score:3, Interesting)

    by nwbvt ( 768631 ) on Saturday July 30, 2005 @10:45AM (#13201989)
    The Romans were the last bunch of people to mess with the calander? You mean nothing concerning it has changed since the fall of the Roman Empire? I seem to remember something about some guy named Gregory in there somewhere...

    And does this mean the Romans had leap seconds where they adjusted their atomic clocks to keep in synch with the sun?

    I know much of /. will be complaining about how this is about the Bush Administration attacking science in their quest to please big business, but in reality from a purely scientific stance this makes sense. The definition of a second hasn't been linked to the Earth's orbit since 1967, so why should we keep on pretending it still is?

  • Actually the last people to muck with the calendar were the Catholic Church, not the Ceasars. The current system of leap days and leap years was adopted by Pope Gregory (as in Gregorian Calendar) sometime in the renaissance. The Orthodox world clung to the Julian calendar leading to things like "Orthodox Easter" in late April/Early may and the "October Revolution" happening in what the rest of the world considered November.
  • Remember when someone thought it'd be a good idea to change Pi to equal exactly 3? http://www.straightdope.com/classics/a3_341.html [straightdope.com]
  • If we bomb France, we might be able to eliminate the metric system altogether. Did you know that the French are hiding the kilogram at a place called Sevres? Not only that, but it is made of platinum and iridium. I'm pretty sure it's a disguised nukular bomb or some other kind of WMD. Designed to take our freedom away, millimeter by millimeter.
  • With the moon having an exactly 24 hour rotation around the earth, would it not be better to switch to a lunar calendar and not worry about leap years...ever? No calendar correction would ever be necessary ( unless a something messes with the moon's orbit, and that has not happened yet ).

    Doesn't this 'keep it simple' approach sound better than 'keep bandaiding it'? Yes, it is a huge switch as opposed to a minor ajustment, but you would never have to adjust again, and all of your time-keeping processes woul

  • I have a hardcopy of a book called the Timing Reference Handbook. It is a fairly length tech note from a company called Austron, who got bought by Datum, who got bougth by someone else. At one point I know it was available as a PDF, but a quick search at the Datum website didn't reveal it, though. The interested party should be able to dig it up.

    The book describes the difference between the various time bases (UT0, UT1, UT2, UTC, atamic time, etc) and gives some pretty good detail about why we have lea

    • Re:Really Good Reference on Time (Score:4, Informative)

      by Teancum ( 67324 ) <robert_horning&netzero,net> on Saturday July 30, 2005 @12:15PM (#13202371) Homepage Journal
      By far the best resource I've ever seen concerning time and navigation is: http://tycho.usno.navy.mil/ [navy.mil]

      This has everything you mentioned above, plus some very current research, the role of the USNO in the GPS satellite constellation, and even the history of timekeeping in the USA. On the whole an excellent resource to look at if you want to know more about time.

      Whenever I setup a new system, I usually drop by their "what time is it" to set the clocks on systems (especially if I don't want to download or enable a nettime client). It will get you the correct time +/- 30 seconds with the web interface, which is as good or better than most casual users really care to get it anyway. Usually far more accurate than most people's watches as well.

  • Good question from a lazy asker... (Score:3, Interesting)

    by Bradee-oh! ( 459922 ) on Saturday July 30, 2005 @11:30AM (#13202187)
    I'm too lazy to go Google it right now, but I think the point is pertinent/interesting to this crowd -
    With our current system of leap seconds, does the Unix timestamp actually reflect the CORRECT number of seconds since Jan 1st, 1970?
     
    Sure some of the Unices are probably different but I'm guessing that many of the implementations of the algorithm calculate the seconds with basic math using only leap years as the deviation from standard.
     
    Ah, hell, maybe I'll go google it, too, but, I'll still ask here. :P

    • Re:Good question from a lazy asker... (Score:4, Informative)

      by scruffy ( 29773 ) on Saturday July 30, 2005 @01:05PM (#13202628)
      Unix time increases by 86400 each day, no matter whether there is a leap second or not. From the Wikipedia [wikipedia.org]:
      When a leap second occurs, so that the UTC day is not exactly 86400 s long, a discontinuity occurs in the Unix time number. The Unix time number increases by exactly 86400 each day, regardless of how long the day is. When a leap second is deleted (which has never occurred, as of 2004), the Unix time number jumps up by 1 at the instant where the leap second was deleted from, which is the start of the next day. When a leap second is inserted (which occurred on average once every year and a half from 1972 to 1998; none at all have been or will be inserted after Dec 31, 1998 up through June 30, 2005), the Unix time number increases continuously during the leap second, during which time it is more than 86400 s since the start of the current day, and then jumps down by 1 at the end of the leap second, which is the start of the next day.

  • It's easy to see where this is coming from... (Score:3, Interesting)

    by Stonan ( 202408 ) on Saturday July 30, 2005 @12:25PM (#13202437) Homepage
    Potential errors in adding 'leap seconds' is causing screw-ups in computer systems. The main cause is sloppy programming so eliminating them makes everything better. Don't have to worry about it for 500-600 years.

    Ask yourself who benefits from this. The only answer I can come up with is software programmers, specifically OS programmers (programs usually read what time the OS is reporting). Which OS manufacturer has the most clout with the US gov.? Which company is reported to have the most liquid cash? To take a quote from Mr. Moore: Who your Daddy?

  • Egotistical maniac? (Score:5, Funny)

    by jrumney ( 197329 ) on Saturday July 30, 2005 @12:38PM (#13202491)
    Once there was a boy, who longed to be as well known as Julius Caesar. First he gathered his legionnaires and started some wars, but he didn't get the respect from the public he wanted. Then he had a brilliant idea. Julius had a calendar named after him, maybe he could get one too. All he had to do was come up with a plan to show those pesky scientists that time was controlled by God, not some mathematical constant, and if God wanted it to jump ahead by an hour every 5 or 6 hundred years, then dammit, that is what is going to happen. He decided to call his invention the Dubyan calendar, because if he called it Georgian, people might give his daddy credit for it, or even worse, some limey king that died last century.

  • The Naming of the Months (Score:3, Interesting)

    by Beolach ( 518512 ) <beolach@NOsPaM.juno.com> on Saturday July 30, 2005 @04:26PM (#13203745) Homepage Journal
    Heh, I found this link [wikipedia.org] in the /. synopsis very interesting. The Naming of the months is something that has interested me & I've speculated on a bit. I knew that the first months were named for Roman Gods:
    Janus [wikipedia.org]
    Februus [wikipedia.org]
    Mars [wikipedia.org]
    Aphrodite [wikipedia.org] (actually a Greek goddess, but the Romans identified their [wikipedia.org] gods and the Greek gods together)
    Maia [wikipedia.org] (another Greek goddess, the Roman name is Bona Dea [wikipedia.org])
    Juno [wikipedia.org]

    I also knew that July and August were named after Julius & Augustus Caesar. After August, the months are named with their numbers.
    September (7)
    October (8)
    November (9)
    December (10)

    But wait! Those numbers aren't right! And here began my speculation. I figured the Romans (like most 10-fingered humans) were fond of 10 (X in Roman numerals), so they may have started with 10 months (which actually is the case). I also assumed that August and July were the last months added to the calender, based of their being named after Julius and Augustus Caesar (this assumption turns out to be false; January and February were the last months to be added to the Roman calender: the Romans originally considered winter to be monthless). I found the (incorrect, of course) conclusion of my speculation to be rather humourous: the Roman calender began with ten months, until Julius Caesar came along, and decided he was important enough that he deserved his own month, and so he created July. He wasn't arrogant enough to think he was more important than the gods, but he was more important than just a bunch of numbers, so he sticks July after the months named after the gods, but before the numbered months. That changes the numbering, but the names from the old numbering stuck. Augustus Caesar dittoed Julius Caesar.

    Sadly, the explanation based on research rather than speculation that Wikipedia gives for the number mismatch is not so humourous. They simply say that March was originally the first month. But I always thought (incorrectly, it seems) that January was named for Janus, the god of Beginnings and Endings, because it was the first month of the year, that marked the end of the old year and the beginning of the new year. But even when January became the first month, it wasn't because of Janus, but rather because the Roman consuls had a year long term, and took office on the 1st of January.

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