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Vote To Eliminate Leap Seconds
Mortimer.CA writes "As discussed on Slashdot previously, there is a proposal to remove leap seconds from UTC (nee 'Greenwich' time). It will be put to a vote to ITU member states during 2008, and if 70% agree, the leap second will be eliminated by 2013. There is some debate as to whether this change is a good or bad idea. The proposal calls for a 'leap-hour' in about 600 years, which nobody seems to believe is a good idea. One philosophical point opponents make is that the 'official' time on Earth should match the time of the sun and heavens."
Just hang on a sec....
Can't we just find something that divides nicely between the time it takes light to travel between the sun & earth and the amount of time it takes for the earth to circle the sun once?
:)
I really liked the Swatch "Internet Time", but I had doubts about its mathmatical soundness... however, wakingup at 250, having lunch at 500 and going to sleep at 750 would be nice
We call this "putting off the problem".
We can ignore the problem then too. Eventually, morning and evening will be on different days. We might just gain or lose a whole day. Heck, we can ignore the problem forever. We'll be off by a year, then a decade...
I've been keeping time with my sundial and temple-top observatory the way Ra intended! Damn you kids and your new-fangled timekeeping.
I thought of this issue years ago, and had actually sat down and done the math at one point... basically, to solve the time discrepancy, just slightly lengthen the second. Everything lines up. Of course, every book, piece of software, scientific instrument, medical equipment, ... well, basically everything in human civilization ... would need to be re-build, re-calibrated, re-programmed, re-manufactured, etc. If nothing else, we'd stimulate the living hell out of the world's economy.
How about going the other way... leap microseconds. Many times during the day. Then nobody will hardly notice.
A leap minute every 10 years (or so)?
One event every 10 years does not cause lots of disruption, and being a minute out of sync with solar time is not large enough to be a problem. You'd notice an hour's difference if you're in a northerly latitude and have Daylight Saving Time...
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Karma: Chameleon
I live at 5 degrees east. Thus, I know that because I'm at GMT+1, the sun will be exactly in the south at 12:40 PM. If we change to the "leap hour" strategy, I'll have to remember what the offset is now, and that offset will change all the time...
Isn't the point of leap seconds that the Earth doesn't rotate at a constant speed, and doesn't this refute the claim that everything would "line up" under your proposal?
This is why I refuse to set the time on my VCR...
788652 = 2 x 2 x 3 x 3 x 19 x 1153
Yeah, because the best way to to deal with a small problem is to put it off until it becomes a really big problem.
ccalam - acoustic versions of new songs.
I propose that we add another year every 5 million years. Or better yet, another decade every 50 million years.
Or, why don't we just redefine the second to deal with all of this in the first place?
09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0
45 5F E1 04 22 CA 29 C4 93 3F 95 05 2B 79 2A B2
Um... isn't the whole point of this article that some people think it's a good idea? TFS even says there is debate over whether it is a good or bad idea!
Actually, the leap second makes the most sense to me. But a leap hour in 600 years, when we do an entire day about every four years is absurd. If we had to abandon the leap second, it should only be replaced by the leap minute,. Likely few people would notice the time being off by as much as a minute (just don't use that sextant any more, or if you do wear two watches or set your to heavenly time). But time being off as much as an hour would pretty much muck things up (think of the effect of daylight savings time and double it).
I'm an American. I love this country and the freedoms that we used to have.
But that's just the start:
How do we know they're not constant? Because we can measure the variation using atomic clocks, of course.
Are you adequate?
I don't have anything substantial to say, but to me it sounds somewhat like trying to legislate the value of pi. Not exactly the same thing as definition of a time coordinate system is ultimately arbitrary, but it's in the same vein.
http://en.wikipedia.org/wiki/Indiana_Pi_Bill
Yeah, this 600 years stuff is nice but who will remember to adjust clocks in 600 years? It's far better to have an instantaneous solution to the problem than a remote one.
Stupidity is the root of all evil.
The leap second is required because the earth's spin is slowing down in a complex, non-linear way.
Changing the length of the second simply won't work, in a couple of hundred years we'll be right back to where we started again. See http://en.wikipedia.org/wiki/Leap_second for details.
The leap hour is a daft idea, why change something that isn't broken, if a tad inconvenient.
Just use Newtonian physics to calculate the different lenghts of years and days in advance, and adjust accordingly, you could do stretches of a millennium at once. We know how long a year is now, and we can calculate how long a year will be 1 million years from now. So each year or every few years a new set of "yearly calenders" time scales could easily be released. As for software issues with time, software can use a different standard time measurement system, which can manualy be computed into the official "Newtonian corrected time standard system". This way time is always in sync with the solar and galactic cycles and everyone is happy.
Alternatively can't some way be made to extend the very accurate Mayan calender beyond 2012? or Re-use it such as we have this BC AD stuff with the western time thing.
... don't fix it.
This is a bad idea, and my understanding is that it has not much chance of being adopted.
in the 1980s. Nice glasses. I used to have a set just like them...
Yeh, sounds good... I think we should vote to eliminate summer as well... (never liked that season)
'cos I was just getting to the limit of my patience with changing my watch all the time.
Genesis 1:32 And God typed
Why have a leap hour in 600 years time? Surely it would be easier for all countries to just change their local time offset to UTC by 1 hour. So, for example, instead of Pacific time being UTC-0800/UTC-0700, it would become UTC-0700/UTC-0600. (Or maybe 0900/0800)
Why doesn't the gene pool have a life guard?
Yay, nothing like reliving the thrill of Y2K. Except that we don't have to.
One second in 600 years is about 1/18921600000 or roughly 0.000000005%. In a day, the difference between the two ways will produce an offset of 1/220000th of a second, or about 5 nanoseconds. With the possible exception of atomic clocks, no analog or digital device is this precise.
Since any "precise" timekeeping requires periodical synchronization with the world's atomic clocks and astronomical observatories, we'd only need to change them, and the rest will just pick up the new info. Any "standalone" device that does not rely on the above synchronization has a much bigger margin of error than this change would introduce, so they will not be affected.
Yes, you can argue that in 60 years a machine not running the updated time would be 1/10th of a second behind a machine that does and in a deeply hypothetical scenario it could possibly cause some problems, but if the machine is not synchronizing to begin with, its own imperfections will result in a much larger discrepancy than 1/10th of a second in 60 years caused by the time change.
I don't really care what they do with leap seconds, but IMO their time would be better spent abolishing that routine-breaking, parent-killing, accident-causing abomination which is Daylight Savings Time.
The only benefits I can see is slightly later barbecues in summer and a six-monthly reminder to check smoke detector batteries about the house.
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
This whole time changing business, this is about keeping people awake during the hours that sun is shining, and is not in fact about time.
:)
I guess it's a philosophical argument about whether you want to live and work while it is dark outside hahah.
Don't worry, time will lose all meaning by then anyway.
"Nobody knows the age of the human race, but everybody agrees that it is old enough to know better." - Unknown
Before trains, nobody cared. Very few people care now.
Deleted
We could just fire off some nukes every six months or year to control the orbital speed of the earth around the sun. Just keep tuning the orbit to our atomic clocks instead of vice-versa.
Run computers on TAI (International Atomic Time). Keep it constantly flowing, and never add or remove seconds, as per the definition. Then simply calculate UTC in software from a published leap offset between the two, which compensates for the leap seconds:
UTC = TAI - leapseconds
Then define all the timezones off of UTC as normal. All this basically does, is make the calculations for the timezones into a few hours plus or minus a few seconds. This makes a lot more sense, because then you actually have a fundamental time (TAI) which doesn't have discontinuities, but if you want to consider your astronomical orientation, you look at UTC or your local time. We don't need to redefine these types of time, because these already exist. We just need to use them more intelligently.
Honestly, this is ridiculous. First of all, if you time allways is shorter and we're constantly adding seconds, why not introduce a new measurement of time entirely and use that for precision needs while we're at it? Something like 'beats' comes to mind, or a centi-minute linked to max. sun height, which would give a more granular measurement of time at the same time. Take that new technical measurement and sync that to whatever you want.
... it isn't that there aren't enough. Otherwise get over the fact that nature isn't a model, it's reality. And your clocks should represent thatas closely as possible. My 2 cents.
As far as I understand, nature is so "irregular" that the need for leap-seconds can't really be predicted that precisely. What we need then is some signal to announce leap seconds that is stored in every TAI linked clock. That way we can system-internally look up if some timing problem occurs what may have caused it. On second though, everybody can just have his system do some double checks whenever his clock jumps from 24:00 to 00:00 (that's the way leap seconds are allways filled in).
And coming to think of it, given that PCs to date have timing systems that aren't worth squat I think this really isn't that much of an issue for most admins. Hail to Apple for integrating a quartz clock into their systems - others appear to dumb to do that. Finally I can read the time on my Computer and trust it too.
Bottom line:
The Sun will allways be "out of sync" with whatever measurements of time we come up with. Honestly folks, she really doesn't give a f*ck. If you need precise timing, pick one. Unix Era, UTC, TAI,
We suffer more in our imagination than in reality. - Seneca
I think it would be soo much easier to throw away our clocks & base everything on the number of seconds since 00:00:00 January 1st 1979 from now on.
Come on it's been nearly 2008 years since we had BC, it's time for a change !
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If one little (leap) second is worth all the fuss, where's the uproar to finally rid us of the dangerous practice of needlessly, senselessly changing almost all clocks in existence (in an age where every other gadget has one) twice a year by one whole whopping hour , with all the trouble that entails?
There were 240 pence to the old (pre-decimalisation) pound, comprised of 20 shillings each worth 12 (old) pence. Do you remember guineas, crowns, half-crowns, shillings, tanners (6-penny piece), threepenny bit, pennies, half-pennies, farthings (a quarter penny)? I do. I suspect that I am quite a bit older than you and I cannot ever remember there being 120 pence to the pound. So either please provide a citation or confess that you are mistaken/talking bollocks. :-)
But the main thrust of your post was correct with regards to dividing sums of money easily. Or at least it was until the education system decided that mathematics and mental arithmetic were not the most important subjects in life. I'm not sure how some of today's young people could cope with such problems.
Have a look at soylentnews.org for a different view
All unix and linux systems encode their times as offsets from 1970-01-01 UTC ignoring leap seconds. That results in times that have no available time encoding. It was probably wise (or necessary) to define it that way because the leap seconds cannot be determined algorithmically.
Most applications would probably have no problem interpreting leap seconds as NTP time adjustments. However, I suspect it might already give trouble to many kinds of precision devices and possibly increasingly so in the future, when realtime controls of all kinds of machinery are tied to the steady flow of time. Critical bugs practically write themselves when some components meticulously take the leap second into account while others ignore it.
I do think it would be better to replace leap seconds with a leap hour. It can be handled painlessly returning from daylight saving time, and programmers can be given ample warning (say, a century).
It will be put to a vote to ITU member states during 2008, and if 70% agree, the leap second will be eliminated by 2013
Given that the representatives of each member state are presumably experts on chronological matters, this seems like an insane idea: making a change when 30% of experts think it's a bad idea doesn't make sense.
"If you think the problem is bad now, just wait until we've solved it." --- Arthur Kasspe
sure, [eliminating leap seconds] may save a few lives... but thousands will be late
Mongrel News all the news that fits and froths
I bet it would be a considerable challenge to find 12 watches synchronized within 30 seconds of each other. So we're worried about seconds of mismatch between sundials and the only computer on earth that isn't connected to the internet? I agree with the article. Leave UTC time alone and synchronize to GPS time instead. The rest of the world will go on being happy having their watch within a couple minutes of the "official time."
New! Device Legs: These legs will help your poor OEM installed product escape any hamfistedness it may encounter. Ava
When's the vote to eliminate Monday to Friday?
I think this is very bad idea since all the clocks will be inaccuare within 1 hour in next 600 years.. Inaccuracy will rise and rise..
But all it did was lengthen the working day and for some people, the working week (as in +6days for the smart alec's out there). Now you are stealing the time out of my days one second at a time.
WHEN WILL IT END?
Half the world throws their clocks off by an hour for half the year already.
Do we want time functions that constantly have to change... do we need a massive table/rules to work out long range time diffs?
Just as bad as time zones changing often, its going to really require people's code is correct, otherwise we have slight differences somewhere... even if it is small.
Liberty freedom are no1, not dicks in suits.
*Of course over here we've since split from Sterling and subsequently gone the way of all Europe
"Linux is for noobs"-The new MS fud strategy
This is starting to sound a little like medieval astronomers arguing about a href="http://en.wikipedia.org/wiki/Epicycle"]epicycles[/a]. We've got a lot more knowledge, but the folks in our future may look at these debates the same way.
I wonder what new breakthrough will render these discussions unnecessary. This isn't bad science, but it's very possible we've got a bad theory somewhere in need of tweaking.
--
Toro
Inherently, those who want to get rid of leap seconds also want to get rid of time zones (at least they indirectly do).
Having our clocks NOT agreeing with astronomical time, completely eliminates all the benefits of time zones.
Whether you actively think about it or not, our sense of direction is substantially driven by the combination of our clocks, and the Sun. We use it as a reference all the time (why do you think it's harder to find your way in a new area, when it's dark?). Even if there's no other defining features, there's still the Sun to tell us which way is North (or South), and our clocks give us a reference to relatively where the Sun should be. Subtly change someone's clocks, and you'll see them having a slightly more difficultly with their (otherwise good) sense of direction.
Seems to me, the only argument here is that there are a few groups who _really_ just happen to need TAI time, but they see that it's just much easier to access sources of UTC time, and so want to redefine UTC (eliminating leap seconds) so that it is monotonic, and strictly corresponds with TAI at all times. Did I miss anything?
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
The Earth wobbles.
Clear, Dark Skies
But a guinea was 21 shillings = 105 new pence, not 120
Does anybody really know what time it is? Does anybody really care?
Whaddya know, the USA moves at a meeting in Texas that something scientific is just too hard to understand and should be dumbed down.
the value of hours minutes and seconds, so that we don't have to have the leaps in the first place. Solve the problem: a day is not 24 hours.
I think this is a perfect opportunity to propose the switch to metric time again, aka Swatch time! Or maybe we can adopt decimal time instead.
This guy's the limit!
Ultimately if you think about it I fail to see what the earth's spin really has to do with the notion of time.
;)
You what? Geez, time to leave your mother's basement for a while, you might discover something know as the day/night cycle. And if you spent some more time outside you might discover the things called seasons.
Definitions of time are really very, very arbitrary.
No they're not. A day is one rotation of the earth around its axis. A year is one rotation of the earth around the sun. The definitions are as clear now as they were several millenia ago.
Mankind is so good at ignoring nature to create arbitrary defined units of measurement, I don't see why all of a sudden the notion of time needs to be in harmony with the Universe As We Know It (tm).
Did you actually finish highschool? Or the british equivalent?
All "arbitrary" defined units of measurement are ways to model the "Universe As We Know It (tm)". As our knowledge gets better, so does the acuracy of these "arbitrary" units. To not update the model we have of the universe to new knowledge would be to utterly fail at science. And time has allready been redefined. A second used to be defined as the 1/86400 part of a solar day, but is now defined in terms of radiation of a caesium atom.
Finally, TFA has little to do with the definition of time per se, but more with time on earth. We expect the sun to be at it highest point at noon (ignoring silly DST for the moment), but since the earth's rotation is not regular we have to change something. Since it's rather hard to change the earth's rotation we opt for the easy way out: we change the moment of noon. The question then becomes, how often do we change it. So far, we've opted for a miximum drift of 1 sec, if time is off by more we add or subtract a leap-second. TFA is about opting to let time drift for about an hour before we change it. I think that's a bad idea, but then again, what do I know
No more time zones and daylight savings
http://en.wikipedia.org/wiki/Sidereal_time
My rights don't need management.
As much as we play around with daylight savings time, more often then not local earth time and the relative position of the sun overhead don't match anyway. More importantly, it has been even longer since most people cared. The philosophical questions are now moot, the scientific and engineering questions have workarounds (no one measures anything serious in local time, they just convert to it), and all that is left is the question of whether or not we need to expend the effort to adjust our clocks every time they are just one second off from some fully imaginary standard.
...En að Besta Sem Guð Hefur Skapað Er Nýr Dagur
Could someone please copy and paste the contents of TFA. It's in a proprietary file format and Stallman has forbidden me from opening it.
It is dangerous to be right when the government is wrong.
And in the southern half of the universe, things spin the opposite direction!
Well, the sun isn't in highest position now at 12.00 either. So where's the need for one second ? Also the "Daylight Saving Time" is complete waste of effort. Is is based on time when artificial light was expensive. Now the street lights are on anyways all night.
And then we come to the idea that different Time Zones are not necessary. Just try to calculate flight time when flying a longer trip Japan to Australia, when Japan is using Summer Time or Australia is using Winter Time (DST in winter!).
We should all use UTC. We'll soon learn that that day time is not between 6.00-18.00 but 11.00-23.00 (example somehere in US).
The question is what do you want to do with the time of day. Should it be astronomically based? This is not a trivial question.
Many electric grids are required to be timed with accuracy of better than 10 milliseconds. Remote Telemetry Units need to record events with a time stamp that might mean something to an operations control center. The problem is what do you do with leap seconds?
The POSIX standard time epoch doesn't include leap seconds. So you're left with a terrible morass of a problem. Do you do what the NTP deamon does, by slewing the clock at some known rate? The problem with that is that while events remain in sequence, the time between events is not accurate. Do you simply include a second 59th second? The problem there is that events will be recorded out of order and they can't be sorted back.
And yet, many also have legal requirements to adhere to a UTC based time standard.
Ladies and Gentlemen, the problem isn't the leap-second concept. The problem is our damnable entrenched software standards. We're trying to fix this problem by creating another.
Nearly fifty percent of all graduates come from the bottom half of the class!
I have a better idea. Instead of conforming to the sun, let's define a time system we like, then alter the orbit and rotation of the Earth to match the time system.
Global ecological disaster is nothing compared to the nuisance of changing the calendar every four years!
There are two seperate subjects debated in TFS. Read: Subject 1: the removal of leap seconds debate. "..a proposal to remove leap seconds from UTC...There is some debate as to whether this change is a good or bad idea" Subject 2: the debacle of a solution. "a 'leap-hour' in about 600 years, which nobody seems to believe is a good idea" It's fine
And also make the number of days per month the same. And get rid of daylight savings time. I know it's just a time zone change but a lot of us are too lazy to put the time zone in timestamps. Then maybe we can start to make it safe to hard code all those polynomial date calculations in all our programs.
Then after that we can make it illegal to live for more than 99 years so it will be safe to use 2 digit year fields.
"Education is not the filling of a pail, but the lighting of a fire." -- William Butler Yeats
Get rid of daylight savings time too.
The basic idea is not to demand that the year be an integral number of days. The New Year will be "born" at varying times of the day. I clearly remember my mom cooking up the New Years feast and then waiting patiently for the new Year to be born, which would shift by about 6 hours every year. The Hindu calender will state the next new year, "Sowmiyan" or "Sadharanan" (there are 60 named years) will be born at 1:06 PM or 7:36AM or whatever. Typical South Indian New Year will begin on April 14 for about three years (like 7AM, 1PM, 7PM) and on April 15 (1AM) for a year and then the leap year in western calender will bring it back to April 14.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
I believe the earths rotation should be adjusted to match the second. Cannot be so difficult. Even Jules Verne envisioned it as a possibility (well, an erthquake happened and wiped out e few zeros, but that is another story...).
And it would finally put all these nukes sitting around idly to good use...
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
We should never postpone it till it accumulates an entire day offset: this would be disaster (like having the date changing when the Sun is right above our heads). But an hour in 600 years is totally reasonable (if that's really the case, no time now to read the article). It even may yield significant economies when dealing with second-level-precision events.
:-) Heck, we could split it in two half hour offsets each 300 year to make things even more palatable.
We endure a 100% imbecile thing that is "daylight savings time" which means exactly one hour offset occurring twice every year! This totally damages by biological clock, but I bet even I would adapt over 600 years
*- NOTE: There's a change of subject next. Don't fret, stay calm, please *-
Now that we're at this time theme let me address also the "decimal time" question: it is a good idea, but the basis must be the second and not the day as may propose (they want a day composed of ten or 100 "decimal hours", which would in turn be divided in a 10^n seconds).
All this is somewhat possible, but: the second cannot be changed, because it is the basis of the now nearly universal SI system of units (meter/kilogram/second etc.). So, a day must continue to be made of 86400 seconds -- this is because a day is a natural fact, just like my height. So they cannot be the basis for any unit, because other people heights (or other planets days) would be different. That's also why an inch or a foot as units are bad ideas -- unless, of course, an inch is defined as 25,4mm -- but that's really a rose by another name.
But surely, one can have hours of 1000 seconds, no problem. This Babylonian 60-based math with 24 units for a day certainly suck.
Yeah, everytime we have a leap second, it really ruins my day. We need something much less noticeable. When was the last leap second again?
Astronomical time is used as a guidline only.
Check the coast of Canada (Newfoundland) or the situation around Indonesia. Uuuuuhhh mama...
http://upload.wikimedia.org/wikipedia/commons/3/3d/Timezones_optimized.png
Mit der Dummheit kämpfen Götter selbst vergebens
That would be an interesting transition period as people got used to indicating or recognizing the numbers 4 or 128...
All editorial writers ever do is come down from the hill after the battle is over and shoot the wounded.
This makes UTC more useful for a very small number of people ... yet it will make it completely useless to most people in a decade or so.
... can deal with leap seconds.
... can't do without leap seconds.
Legacy systems which need absolute time now and use UTC
Legacy systems which need something resembling mean solar time now
Why change it instead of making a new standard for new systems which need absolute time? It breaks nothing and accomplishes the same goal. I fail to see the logic in the present change, except for the fact that it will make some people a lot of money since huge amounts of systems will have to upgrade from UTC to whatever new standard emerges to take it place for use by most of us.
Science just isn't as great as it likes to make out... There is a scientific solution of course, but accountants and managers get their way and so we have completely brainless ideas like leap seconds...
And of course, global warming slows down the earth's rotation by moving water from the poles to the equator.
A true engineer would shift mass back to the poles from the equator to fix the issue...
A truly great engineer would calculate just how much mass to leave off a bridge construction somewhere in China to fine-tune the seconds each year to compensate for people moving house and shifting location all around the world.
A really truly great engineer would shift massive amounts of earth from the equator to the poles to make the earth shaped like an Australian football so the earth's rotation speeds up and we can all leave work early each day.
But the second is sacred... And leap seconds are just toooo easy.
Only good for accountants and managers.
GrpA.
Enjoy science fiction? "Turing Evolved" - AI, Mecha, Androids and rail-gun battles. What more could you want?
I haven't read the rebuttal but here's some reasons why they should keep it as is.
1. By keeping inaccuracy to below 1 second, human-set clocks and pcs that sync to an atomic clock are all always within about a second or so.
2. Keeping time is useful for being able to navigate with solely a clock, a compass and the sun.
3. Shadows could get out of whack, ruining sundials.
4. Humans generally experience time at a granularity similar to that of the leap second. Computers also have power up/down events, however for a limited period of continuous high resolution time they can use TAI or just turn off their ntp sync until the end of the period.
5. A disparity on the order of several to tens of minutes in the length of a day or noontime position will be discernible and could cause psychological stress or anxiety. News reports will heighten that.
6. Star charts and possibly existing navigation systems could get out of whack.
Hammertime?
Please read my Canon EOS tech blog at http://www.everyothershot.com
All I know of the Irish monetary system is what my neighbour told me. Something along the lines of, if you wanted a pound, you had to have X in coppers, or Y in silvers, where X did not equal Y, or any integer multiple of Y. I'm not sure if it was completely true, or if I'm remebering correctly, but I do remember that it was really messed up.
Anthropic principle: We see the universe the way it is because if it were different we would not be here to see it.
Historically, there have been some 30 Februarys: http://en.wikipedia.org/wiki/30_February
"If you think the problem is bad now, just wait until we've solved it." --- Arthur Kasspe
While we're at it, there should be a few more items on the agenda. Let 'em vote on the speed of light, speed of sound, atmospheric pressure at sea level, etc. With any luck, they'll pick values that make calculations really easy!
Gee, won't this screwup the time traveller's navagation?
All of our software uses GPS time as a time reference. All of our data is timestamped with GPS time. When a conversion to/from UTC happens, the software uses a hard-coded leap-second table to apply the correct UTC-GPS offset. When a new leap second is announced, someone has to remember to go update the table and rebuild the software. Not the best scheme in the world, but the software is close to 20 years old.
There's no other way to compute the elapsed time between two events unless you use a continuous time scale.
In the course of every project, it will become necessary to shoot the scientists and begin production.
We should just a have a global time-server that dictates the time. If communication breaks down, we're in deep sh**t anyway.
Won't somebody think of the sundials!? I mean, c'mon! Sundials are cool and important! And what about Stonehenge?
Actually, I'm in favor of keeping UT1 and TAI in sync. But not for the sundials
Does your significant other love shoes?
Leap seconds are seconds of inaccuracy that get corrected every several years in UTC time systems.
/should/ all be tracking time in UTC time and then doing local timezone corrections (Linux does this by default, for example) in which case a file timestamped after another was always actually created after that previous file. There are otherwise weirdnesses that show up in tracking "beforeness" and "afterness" on computers when time changes occur.
Leap years are entire days we add to the calendar once every four years to let us have calendar years made up of regular numbers of 24 hour days 3/4 of the time.
Daylight savings time is a totally unrelated issue where we change what our local clocks say. UTC is completely unaffected as it ignores local time entirely.
Computers
- Michael T. Babcock (Yes, I blog)
When I first heard of this wacko idea, I thought it
was yet another aspect of the anti-science bias of
the present US administration. I didn't realize it
had spread around the world.
Think about it: it's yet another attempt to believe
something that is detached from reality.
It's really no different from legislating Pi to be
"3".
No I don't, because I don't know it! A horse is a horse of course of course, and no one can talk to a horse of course ...
RETURN without GOSUB in line 1050
"It is inappropriate to require that a time represented as seconds since the Epoch precisely represent the number of seconds between the referenced time and the Epoch." - IEEE Standard 1003.1b-1993 (POSIX) Section B.2.2.2
Keep UTC with the leap second. Civilian time can use that.
For UT1, eliminate the concept of hours, days, etc. Time will be told by the second only. Maybe even call it something else like a "chron". You can talk about hectochrons, millichrons, kilochrons, etc. In fact, start the counting of "chrons" at January 1, 1970.
Now, if you use chrons, there is no more link between days or years, and no more leap seconds. Computer systems like GPS or space travel which get thrown off by leap seconds, but don't really depend upon the concept of "day" or "year", can use chrons. People who depend upon the astronomical time can use seconds and live with leap seconds. To each, their own. And, converting between the two units is quite really simple.
The real silliness of the whole proposal is that these scientists actually think their decision will eliminate the leap second. Astronomers will simply ignore the whole thing and go back to GMT. So will all the governments which means all the atomic clocks will still use leap seconds. UTC will simply disappear, and we're back to square one.
Why don't we just make every second 0.000019013243% longer? Seems simple enough to me.
(By the way, that's 1/(600*365.2425*24), where 365.2425 is the average days per year over a period of 400 years.)
In the Hebrew Calendar we have a leap month. 7 of every 19 months. I don't follow that calendar except to find out when the major holidays are but its explained here: http://en.wikipedia.org/wiki/Hebrew_calendar
That length was divided into 24 hours, each of which was subdivided into 60 minutes, then 60 seconds, and the exact time represented by a second was fixed. Then we found out that the length of a day is getting just a teeny bit longer, and the accumulated error amounts to a second over the course of a year or more. Or maybe the original measurements were off by that much.
Whenever the astronomers determine that things are far enough out of whack, they declare a Leap Second to try to keep the average time of noon the same. They either add a 23:59:60 right before midnight on the last day of a quarter (so far only Dec 31 or Jun 30 have had this honor), or theoretically could omit 23:59:59 (but this has yet to happen).
Otherwise, 12:00Z will no longer be mean astronomical noon at the Greenwich Observatory, which is pretty much the point of having a Prime Meridian in the first place.
[100% ISO 646 Compliant]
SVM, ERGO MONSTRO.
I'm sure I speak for every programmer on Earth when I scream, "STOP MESSING WITH TIME!" It's hard enough to deal with dates and times when going between TAI and UTC, and keeping around a leap seconds database, but the code out there works.
... because they really _can_ party like it's 1999.
(Disclaimer: It's actually 2000 in Ethiopia, but when am I _ever_ gonna have a chance to use that joke again?!)
You are in a maze of twisty little passages, all alike.
Can't we all just run our clocks on Moscow time?
If you don't know what AltaVista is (was), get off my lawn.
Lets just make the Second 1/31536000 longer. Then no need to adjust all the time.
That the President has proposed defining pi as exactly 3, to ease the burden on elementary math teachers.
The society for a thought-free internet welcomes you.
If leap seconds come too often, and leap hours allow the time to diverge too much, how about leap minutes? Official time doesn't deviate from solar time by much, and yet we only need one every hundred years or so.
Of course, this doesn't fix the real problem: that the Earth's rotation is gradually slowing, so any system based on a foundation with a fixed number of fixed-length seconds will always become gradually more unwieldy.
Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
You can't take the sky from me...
Why is this an issue for air traffic control? All computer systems
must have methods for setting the clock, and this necessarily
involves clock skew. There's no getting around the problem
even if there were no leap seconds.
Even atomic clocks have "skew" depending on where they are
in the gravitational field.
Rather than submit a stupid proposal to eliminate clock skew, it
seems a better proposal would be to publish agreed methods
to deal with it.
Where is Albert Einstein when you need him?
It only really matters if you go outside, and what geek does that?
Engineering is the art of compromise.
I own and love this shirt...it's purely educational!
With the first link, the chain is forged.
The Orion Queen is going to return to destroy us in 2012, so I'm guessing whatever is left after that will begin a new calendar system anyway. So this is really moot.
Only three things are certain; death, taxes, and apocryphal quotations - Ben Franklin.
Just get rid of time altogether... no more problems!!
There is billion of reason to keep leap second.
Network timing must adapt to that or use it's own Network Time that is not UTC.
The calendar used by the Jewish religion for thousands of years provides a very interesting solution to the problem of synchronizing the way we keep time with the phenomena of the universe. First, the calendar is based on both the sun and the moon. The sun provides the annual cycle which includes seasons, as well as the daily cycle which includes sunrise and sunset. The moon provides the monthly cycle. Because the moon and the sun together create a pretty complicated pattern, this calendar has a slightly different setup each year, and its cycle repeats every nineteen years. This synchronizes the sun and moon, the daily cycle and the seasonal cycles. Furthermore, because days are shorter in winter and longer in summer, time is kept using a proportional hour. An "hour" in this timekeeping system is defined as 1/12th of the amount of time there is daylight. So an hour in winter might be as short as 45 minutes, and in summer it might be as long as 1 hour and 25 minutes. This calendar and timekeeping system is still in use, and has been for thousands of years.
It would be cool if we kept time this way. It would mean that your computer would work faster in the winter, since the definition of a nanosecond would be such that more processor cycles would elapse per fixed unit of time. This makes sense since the cooler weather of winter would help in terms of processor cooling due, which would be necessary given the increased speed in winter.
No matter how this is resolved, in the end Microsoft will screw-up the time zone patch.
has something to say
Can I have your liver then? D.
It will end when you set up your own business. As long as someone else controls you, time savings due to technology will usually be used against you.
This only applies to GMT. So unless you live in Greenwich, it's not a big problem, now, is it? ...
In all seriousness, though, Windows XP uses local time instead of UTC (giving me two copies of many of my files when I back up). I wonder whether this has implications for leap-second implementation.
- RG>
Hey pal, this isn't a pleasantforest, so don't waste my time with pleasantries!
I think this binary thing is a good idea, but it still hasn't provided me a clue... What is the significance of the number 128? When I'm out driving, a lot of people stick there hands out the window and flash "128" at me.
Solar time (ie. sun at zenith at noon) only happens along 24 specific lines of longitude, one for each time zone. Unless daylight savings time is applied, and then it doesn't match anywhere that it's applied for about half the year. That specific line of longitude shifts with the earth's procession and distance from the sun. The "time should match" argument has big holes.
Clock time being arbitrary, I think the whole world should run on one time standard. The US military uses GMT world wide and calls it Zulu. Whether the sun is at zenith at noon in Greenwich would make little if any difference to the world.
The USSR ran on Moscow time despite covering almost 180 degrees of longitude. It pissed some people off, but it was never one of their many serious problems.
If astronomers want to use corrected sidereal time, let them, and let them correct it however they want. It doesn't match solar time anyway.
The argument that navigation requires accurate time has been moot since GPS became available.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
"The only reason for Time is so that
everything doesn't happen at once."
- Dr. B. Banzai
Our time system is completely screwy -
60 seconds
60 minutes
24 hours
AM/PM, leap years, leap seconds, EST, EDT, GMT
basically it is a system that evolved collectively from a bunch disparate, non-reasoned decisions.
(NB, the date system is even worse. 7, 28,29,30,or 31 days)
instead of arguing over how to fix a broken system, design one that makes sense, and get people to start using it.
I'm not an expert in such things, but there are many who are.
Here's what I think:
Frankly, seconds are too short for people to do anything with, so we don't use them - they are dropped.
Minutes are too short to schedule a meeting - so people fudge them, and come 5-10 mintues late.
I think we should have 10 major units in the day (0-9), and within each 1/10-of-a-day block, you have 20 7.2-minute blocks, (A-T), reserving later letters for corrections at various times of the year (yes, a totally english-centric view). Smallest increment would be 1/100th of the 7.2 minute block (00-99), or about 4.32 seconds, which would still be dropped usually.
Benefits:
This would allow you to specify useful times through the day with only 2 characters (like 5G).
You could specify exact times with 4 characters: (3R19) (8U21) etc. (instead of 9 now)
Consulting time would be billed in 6-minute blocks (as most people do now anyway).
The primary useful unit would be 6 minutes, not 1 minute - a block that conforms better to human norms.
People would be less stressed about being on time, given the units are longer.
Get rid of AM and PM and the choice if people use AM/PM or 24h times.
If we align at midnight like we do now, daylight hours are in a friendly, linear block of numbers like 3-7.
And as I said, I'm not an expert- I came up with this off the top of my head. Others could probably do better than this even. One would have to fix the verbal communication of single letters which is always error-prone. breakfast at 3B and 3P are like 2 hours apart but sound pretty close.
How about a 'leap-day' in about 14400 years?
>we seem to have decided to centre our actual lives around 13:00 instead.
>Switching permanently to DST would fix this
Actually Russia did this a long time ago (check a time zone map).
I remember a scene in "One Day in the Life of Ivan Denisovich"
by Alexander Solzhenitsyn, where one character considers how stupid
it is that the sun is highest at 1300 instead of noon. I couldn't
agree more.
You know, I've been doing data entry for years...and at a decent speed. Until you said this, I didn't realize that I'd been hamstringing myself.
I've found that, oddly enough, I seem to only type with the middle 3 fingers on each hand, plus the pinkies for shift, and left thumb for space. Granted, my hands are fairly big (I can hit Q and P at the same time with one hand without use of the thumb), but it surprised to see that the pinky stays up in the air on both hands while I type. I guess I never bothered to look after so many scoldings while learing on a typewriter.
Thanks for the interesting test!
The American Dream has too much grinding and the leveling makes no sense. -GameboyRMH (1153867)
Seconds leap YOU!
:)
Sorry. Couldn't resist.
I hope they have not been calculating when to add a leap second in years gone by, but I think they have and that's why the seasons all start a little earlier these days.
Why a leap-hour in 600 years when over the past 35 years you only had 22 leap seconds? That amounts to 377 leap seconds in 600 years. 377 seconds is (as any toddler will tell you) 6 minutes and 17 seconds.
The leap-hour isn't due in 5727 years.
Somehow I don't think civilization will get that far, at this rate. If we think we will, than I vote not to take this option. One hour is too much not to notice. Keep the leap second, nobody notices it, except for higher science, who will just have to hold their breath one second.
It seems a valid concern, but I do not often encounter cron jobs running every minute, so applying the leap minute at [0-5][234789] minutes past the hour would avoid 99.9% of all these concerns.
(Apologies for any regex blaspheny I may have committed above)
Donte Alistair Anderson Roberts - hi son!
Karma: Chameleon
UCT = universal civilian time, which is UTC with epsilon to UT1 increased to a large enough value that it becomes possible to publish the leap second table 20 years in advance. Because this only needs to accommodate future *uncertainty* of the earth's rotational period (taking into account the known decay term), I imagine epsilon wouldn't be much greater than 5s in practice, but it would require some fancy math and quasi-speculative models to determine probable bounds.
There is plenty of reason to keep civilian time on solar terms. I've been reading a lot of research lately on the importance of circadian phase to human health. We need a civilian standard consistent with civilian health.
If this does not work for the mil/aerospace industries, they can decide their own standard in relation, just as long as they don't redefine a known standard under an existing name.
As far as continental drift is concerned, that's a matter of establishing civilian leapzones with respect to the astronomical divisions. Ordinarily, the analemma that determines whether midnight is mid night doesn't take into account tectonic drift.
A while back I had the notice of also establishing season's saving time. Right after Halloween, we roll the calander back to the beginning of October, then after Halloween II, we fast forward to December 1st, leaving only three weeks for xmas shopping.
If any true geeks remain here, rather than geek-wannabees (how pathetic is that?) or apron-string apers, this is actually a good read:
http://www.math.nus.edu.sg/aslaksen/projects/tsy.pdf
This problem is sooo trivial that the only solution is to abandon our old time system and make a new one (please make it decimal).
This is a simple process:
1. Everyone that cares about this meets somewhere and create a new time system, establishing when the switch will happend 2. Switch to the new time system 3. Everyone start fixing every system that is based on time on earth, this should take a few hours 4. Everyone else that is not fixing the time system, stay at home reading books 5. ??? 6. Profit
"There is plenty of reason to keep civilian time on solar terms. I've been reading a lot of research lately on the importance of circadian phase to human health. We need a civilian standard consistent with civilian health."
If keeping the time constant for health was at all the reason, then making "noon" the constant point of time doesn't make sense. There is no sensory mechanism attuned to the Sun being directly overhead. You should keep dawn or dusk constant and vary the day appropriately.
and it isn't just tectonic motion where UTC falls down. It also fails to consider the periodic variation in the Earth's rotation due to tidal forces from the moon.
The justification for leap seconds is inadequate for the benefit. They don't have to wait for a whole hour to correct, though. Every 20 or 30 years they could do a leap minute. That would be a reasonable compromise.
Intron: the portion of DNA which expresses nothing useful.
half a farthing.
And I've read that a scruple was half a groat. Not sure about that one.
(and for another poster, I thought NTP had 0-60 seconds (the 60 second was the leap second).
You are wrong about "stimulating the economy".
Any economist would tell you that when money has to be spent after a hurricane to rebuild, or for things like Y2K bug, it is not beneficial to the economy because that money could've better been spent on something else. Like investing instead of spending it to redo infrastructure.
Libertas in infinitum