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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?"
but it seems to be working perfectly fine as it is, why fuck with it?
http://leapsecond.com/ -- This guy should complain. They're taking all the fun out of his clock collection!
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?
it's government conspiracy!
My sig is permanently on strike.
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.
Jesus saved me from my past. He can save you as well.
I don't see anywhere in the U.S. Constitution that the government has been given authority over time. I guess strict constructionism applies only to judges and not the government. Bummer... There's never a Time Lord when you need one.
Mod parent funny for its subject, please :D
"Empathise with stupidity, and you're halfway to thinking like an idiot." - Iain M. Banks
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.
http://www.thebricktestament.com/the_law/when_to_
I say we adjust the planet's rotation and orbit so we have perfect intervals.
...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).
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.
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...
... 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...
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
Kent M Pitman
Philosopher, Technologist, Writer
Also, IIRC, before the 1917 revolution the Russians were still using the Julian Calendar. The communists adopted the Gregorian calendar in 1918, which is why the so-called October Revolution was actually commemorated yearly on November the 7th.
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?
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.
Oh, and the "renaissance" is over-rated. The middle ages were the big days when important things were invented - things like representative democracy that you might just have heard of?
Yeah, I've heard of it. Haven't seen it in action yet.
Got Shadowrun? Awakened Worlds
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.
Human genome = 3 billion base pairs = 6 GBit. Windows + Office = 20 Gbit. Which is more impressive?
A leap year would be a whole new year inserted in the calendar, and it's a possibility in the future that something like this may happen.
No, it's not. The point of leap periods is to maintain the length of the day and the year to their astronomical counterparts. Inserting a year would do absolutely no good towards any end as there is no astronomical measurement beyond a year that is used in the standard time measurements.
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?
Mathematics is made of 50 percent formulas, 50 percent proofs, and 50 percent imagination.
>> 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...
http://request-header.info
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 that. Forget time zones - no need for that either. We'd probably go to 24-hour time and ditch am/pm since they'd have little meaning in most regions of the world.
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.
An office on the other side of the country might start work at 1700 instead.
There would be no official countrywide designation of starting and stopping time, although most people would expect businesses to be generally open between sunrise and sunset. In 500 years nobody will care that the whole clock has drifted an hour, since the number on the clock doesn't mean anything in the first place. It is just a reference, and it would work fine for that purpose under such a system.
I can't really think of anybody who would be negatively impacted by such a system other than traditionalists. Astronomers would be fine - their star-tracking software probably calculates everything in some internal time format anyway, since the leap-year/leap-second/23h56m business already makes the current 24-hour clock useless for them. If anything, the software would be easier to design since the rules would be deterministic.
And false. We use the Gregorian Calendar, which was instituted by Pope Gregory XIII. So he's really the last one to mess with the calendar, and as far as I know, he died a natural death.
Not that a little reality will get in the way of bashing the US...
I'm too lazy to go Google it right now, but I think the point is pertinent/interesting to this crowd -
:P
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.
"This is Zombo Com, and welcome to you who have come to Zombo Com" - www.zombo.com
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
when you see the word 'Linux', drink!
I'd be more concerned if they were flying planes with margins of error of less than a second.
Besides- it doesn't matter what the actual time is with technology, but rather the relative time. As long as the planes obey the same second tick, who cares.
-M
when you see the word 'Linux', drink!
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!
Anyone who thinks that leap seconds could pose a problem to computer systems is an idiot!
Chances are most servers do not have the exact time, and if they did, it's probably because they're using NTP, in which case they would get the adjustment without knowing it.
Last I knew, it's impossible for a computer system to maintain precise time over a couple of years. If all your servers have the same exact time, you're using NTP, end of story.
By far the best resource I've ever seen concerning time and navigation is: http://tycho.usno.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.
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
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?
The GEEK shall inherit the earth...
The irony of course is that if we do let the U.S. do whatever the hell it wants on this, as usual, there won't be an Earth 500 years from now, so it really is a good solution.
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.
How dare you speak as if my pangalactic 200 million year calendar has no significance.
500 years ago, people weren't reading, they weren't really doing much of anything productive.
... great grandchildren will grow up to post something stupid on something called the Internet."
& p=2 (the last post at the bottom). Compare that with what you hear people say about Jesus (the non-fireman one).
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
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
While the avoidance of them is super for computers and international business, it sucks horribly for locals all over the world.
Not really. we've already adjusted and programmed computers to deal with timezones. What's the point of making lives complicated for billions of people, just to solve a problem that doesn't even exist anymore?
Speak before you think
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
therein lies the problem. i dont have a compiler handy, so all these numbers are made up (and obviously not correct or even scaled properly, but should at least be in the right order)... imagine second 100000 is 23:59:59 2006-12-31, 100001 is 00:00:00 2007-01-01, and so on. Then second 104729 would be 11:32:17 2007-02-14. but if a leap second is inserted at the end of 2006 then second 100001 will be 24:59:60 2006-12-31 and second 104729 will be 11:32:16 2007-02-14, and so on. this means an extra special case in the time functions, and a displayed time off by one second for people running old versions of the time libraries.
Heh, I found this link 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
Februus
Mars
Aphrodite (actually a Greek goddess, but the Romans identified their gods and the Greek gods together)
Maia (another Greek goddess, the Roman name is Bona Dea)
Juno
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.
Join moola.com, play games to earn money.
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.
Kid-proof tablet..
Assume that most people would be open for their solar day, when it's light out.
If you need to place a call to Zimbabwe now you look up the time, find the offset, and know what time it is there, and you guess if their business will be open at those times. In the new system you'd look up for offset, figure out if you'd be open in X hours, and guess about them based on that. Seems almost identical.
But, it offers a benefit of them being able to say "I work from X to Y" and you knowing what those times are because you work from X2 to Y2, and you can tell when those ranges overlap without doing any math. Then you say "Oh, it's almost Y, I should call the Zimbabwe office." Who cares what the number is?
Really, it's no more of a problem than months. It's summer in Australia when it's winter in North America, and vice versa. This doesn't mean that my Australian friends and I have horrible culture shock when I mention spring break or anything. But, to emulate the currently broken system they'd shift the months and have December when we have June - that way the "Winter" months would always be the same. Of course, whenever you wanted to know the date anywhere you'd need to figure out how many months ahead or behind they were... It'd be a mess.
> What I don't understand, ... why is it so difficult ?
One reason: arrogance!
Both sides are correct: Astronomers and others running systems that need precise synchronization with the sun (or actually with the rotation of the earth) need the existing time system (or perhaps a better one...) Everyone else doesn't, and is better of with a system that is off sync by a few minutes every century and is easier to maintain. There is absolutely no need that all the people maintaining computers for any purpose have to use a complicated system of measuring time that is only needed by astronomers or operators of spacecraft (that seem not to be able to keep their foam in place nowadays...)
The argument is stupid because there is absolutely no reason why two systems representing time cannot co-exist, with precise conversion functions where necessary. Astronomers would sync their telescopes using "Time PRO(TM)" and write their papers an a PC synced to NIST and displaying time using "Time HOME(TM)". Where's the problem. Overall costs would be lower because almost all software and hardware around the world has no need for the complication of syncing with earth rotation to within a second. reliability of time-critic software/hardware would be better because whoever makes them would have to learn more about what time is and not take it for granted. And finally: freeing precise time protocols from the need to be usable by beaurocrats all around the world would probably result later in a protocol that syncs time with earth movement much more often than a second every few years (how about a thousands of a second every few hours, and how about a time representation that divides an earth day to exactly a million equal parts? would be much more practical for controling telescopes or spaceships or sattelites).
The Jewish callendar has 12 months totaling 354 days, so it's not in sync with the solarn year. Every 2 or 3 years a leap month is added. It used to be done ad-hoc by a body similar to NIST. But about 2 millenia ago the system changed by fixing a 19 year cycle. The Muslim calendar is the same without leap months, so every solar year it gains 11 days over the solar calendar, and it cycles every 365/11 solar years. So Muslim holidays are not in sync with the seasons, and muslims celebrating Ramadan in the summer can discuss how it was different when they were children and celebrated it in the winter. There is no problem with all those calendars coexisting, and there are precise functions for converting dates from one calendar to another.
I don't see any problem. I think the US proposition will be adopted in some form without making the old time keeping system go away, the two time systems will coexist, and eventually those who really "need" the old system would devise a new and better system for their needs that doesn't have to make compromises for ease of use by others who don't need it.