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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?
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?
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.
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_
Not really, seeing as old clocks will become even more of antiquities compared to clocks following the newer scheme.
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.
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?
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.
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.
>> 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...
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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.
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!!!"
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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.
"She's a scientist and a lesbian. She's not going to let it slide." Orphan Black
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.
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
Time is a measure, therefore they actually do thave the authority to regulate it. - well, sure in the US. This will just cause more confusion for communications between the US and the rest of the world. But then again, who cares about those prehistoric people, right? (I live in Canada.)
You can't handle the truth.
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
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.