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Leap Second To Be Added Dec 31, 2008
ammorris writes "Don't be the laughingstock of your friends when you shout 'Happy New Years' a second too early ... The International Earth Rotation and Reference Systems Service has announced that a leap second will be added on December 31, 2008 at 23h 59m 60s, meaning that this year will be exactly one second longer. The last leap second occurred Dec 31, 2005; they are added due to fluctuations in the rotational speed of the earth. You can read all about leap seconds on Wikipedia."
I tried to resist, but I still leapt at the chance...
Uhh, wouldn't it be nice if we were given a little bit more of a warning? Say, something like, oh a week?
Gah! I can't take another second of this!
"Kittens give Morbo gas!"
Until 2007 legal time in the US was mean solar time, and that has no leaps, so this is the first leap second for the legal US time. Officially, of course, USNO and NIST were keeping UTC, but that didn't make it legal. The difference shows up in computer time scales.
"Don't be the laughingstock of your friends when you shout 'Happy New Years' a second too early ... this year will be exactly one second longer."
So... wouldnt we be shouting it one second later than everyone else?
Yes, yes, that's Nix vs Hedden and it was ruling by the U.S. Supreme Court in 1893. The court ruled that in the common parlance of the time a tomato was seen to be a vegetable and not a "fruit of the vine", working from the assumption that most people at it for a main course instead of a dessert. I think that if you were going to pick up on the ridiculous nature of the case you'd focus on the reason behind the court case — that taxes needed to be paid on imported vegetables and yet not on imported fruit.
XML is like violence. If it doesn't solve the problem, use more.
Those of us in the U.S. will get to celebrate our extra second during a reasonable time of day, as it's in UTC. The local astronomy museum generally has a baloon drop at that time, so that the kids can feel they celebrated New Year's properly.
Bruce Perens.
If you messed up in 2008 you still have an extra second to make good.
DON'T WASTE THIS GOLDEN OPPORTUNITY!
I work a graveyard shift. You can bet I'll bring this up to the boss. I don't work for free!
If you want news from today, you have to come back tomorrow.
Wait just a second, now! I ... oh.
A truly excellent pizza parlor is a delight unto the heavens. Treasure the sauce and the toppings!
Bush will do anything to remain president just a little longer.
I will be able to give my GF an extra round of pleasure, with time to spare.
/.'er and obviously don't have a GF. But if I did, I am confident in my abilities that I could, in fact, perform my duties in the allotted one second.
OK, just kidding - I am a
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What timezone will it be added to at midnight?
Yes, I know, it is not nitpicking because it's nontrivial for certain high precision science projects... even though I couldn't think of one right now, but it's gonna be quite important for someone.
But just to add a joke: Effin' great, as if daylight saving didn't put enough stress on the mechanics of my clocks!
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Or, is that only in the vista ultimate edition?
I don't suppose this leap second has been encoded into timezone information like daylight saving time has been.
So I would just run ntpd and expect the clock to step 1 second.
At second thought, I would expect ntpd to gradually slew system time since 1s is too small an offset to step the clock at once. Maybe it would be better to stop ntpd and restart it with -g or even delete its drift file since this second is not an error of the system clock but artificially introduced? Anyone know?
Of course it runs NetBSD. BTC: 1NT7QvbetmANwaMzhpVL6
No big d.......eal.
Table-ized A.I.
I'm sorry? Fluctuations in the rotation of the earth? You mean the earth is accelerating and breaking? It has nothing to do with the fact that a rotation around the sun is not exactly 365.25 rotations around our own axis? hmm...
The length of the second doesn't change. An extra second is added. I work with precision timing systems where this is an issue.
The sequence is:
23:59:59 UTC
23:59:60 UTC
00:00:00 UTC
00:00:01 UTC
That means that the valid range for seconds is 0..60 and it is possible to have 61 seconds in a minute. You need to know this if you are using a programming language with range checks.
GPS uses its own time scale that isn't affected by leap seconds.
Mea navis aericumbens anguillis abundat
Yes, the GPS system uses its own internal GPS time which is different from UTC. But the difference is always exactly an integer number of seconds and the GPS system is made aware of the changes to this difference (like when a leap second is added) so a GPS unit can and should display UTC correctly, ie 59, 60, 00.
The UTC second 60 gets added at midnight only at those locations where UTC == local time, i.e. places like England.
For us in the rest of Europe, the leap second will be added an hour after local midnight, i.e. at 01:00:60 CET.
Terje
"almost all programming can be viewed as an exercise in caching"
Uhh, wouldn't it be nice if we were given a little bit more of a warning? Say, something like, oh a week?
You may laugh, but I work in Air Traffic Control. We rely on absolutely precise timing in a system distributed over 1000s of kilometres. Many components can be marked as non-functional by the system if they appear to have an incorrect clock.
Every time we add a leap second we get issues raised. I have to say it is a real PITA.
What I find baffling is that architects/developers working in such a life-critical field managed to conceive application relying on days/minutes which are NOT fixed values. (a minute can have 59 or 61 seconds while a day can have 23 or 25 hours).
That said, the clock of a Un*x system is usually calibrated in milliseconds since the epoch and this has absolutely zero, nada, zilch, nothing to do with leaps seconds. The fact that we decide that 31 dec 2008 with have a 61 seconds minute change *nothing* to the correct calibration of the clock.
How distributed systems across the globe came to rely on hh/mm/ss speaks, well, a lot about the plain dumbness of many people.
But do they really? I pity the poor sick, under-brained people who designed those GPS if they're really that deeply flawed.
Leap years are a separate issue. They keep the calendar in sync with the seasons. Leap seconds keep our clocks in sync with the apparent positions of the Sun and stars.
Mea navis aericumbens anguillis abundat
Leap days and leap seconds serve different purposes.
Leap days are because our definition of a day (and thus a year) are not exact. A year is actually ~365.25 days, so we add an extra day every 4 years to compensate.
Leap seconds are needed as there's another small random variance in the length of a day (The mean solar day lengthens by about 1.7ms per century, due to slowing of the earth's rotation), so we occasionally need to add a second to keep us in sync with astronomical time.
upon the advice of my lawyer, i have no sig at this time
To be subtle, they added the leap second to the one time in the entire year when everyone (at least in that time zone) is watching the clock and counting along with it.
NTP does include leap seconds if your timeserver knows about it, which all good timeservers should do. It shouldn't show up as a slew if ntpd behaves properly, it's a distinct step. Have a look at your logs after midnight and see if it's there.
How many people can read hex if only you and dead people can read hex?
No it isn't. It's a 86401 seconds longer. Than last year. Or 86400 longer than the previous leap-second-year 2005. Oh, yeah, it's exactly 1 second longer than 2004 and 1996.
I confess enjoying myself as a time nazi. Should not forget to count february 29th...
Leap seconds get added all the time. They can't be predicted years in advance. http://en.wikipedia.org/wiki/Leap_second
If you are running NTP or have a radio-controlled lock they will handle this just fine.
If you have a real atomic clock you don't care, atomic clocks never get reset.
Otherwise, you have a couple days to fix your bugs.
Give a man a fish and you have fed him for today. Teach a man to fish, and he'll say "WHERE'S MY FISH, YOU IDIOT?"
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Gravity is a contributing factor in nearly 73 percent of all accidents involving falling objects. -Dave Barry
Um, no, that is not true. Unix time is kept in non-leap seconds elapsed since a defined point in time. Look it up.
Are you adequate?