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U.S. Moves to Kill Leap Seconds

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?"

10 of 601 comments (clear)

  1. now correct me if im wrong by thegoogler · · Score: 5, Insightful

    but it seems to be working perfectly fine as it is, why fuck with it?

  2. Can we say what we will think 500 years from now? by ReformedExCon · · Score: 5, Insightful

    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.

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  3. Best quote of the article by Cybertect · · Score: 4, Insightful

    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.

  4. Astronomers will be unhappy by RayBender · · Score: 4, Insightful
    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.

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  5. Re:Apparently not... by jayhawk88 · · Score: 5, Insightful

    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.

  6. Re:Die - leap seconds - Die! by Anonymous+Luddite · · Score: 4, Insightful

    >> 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...

  7. Re:Apparently not... by tricorn · · Score: 4, Insightful

    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.

  8. Re:Can we say what we will think 500 years from no by PhYrE2k2 · · Score: 4, Insightful

    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

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  9. Network Time? by BobPaul · · Score: 4, Insightful

    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!!!"
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  10. Re:Can we say what we will think 500 years from no by Guppy06 · · Score: 5, Insightful

    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