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The Future of Leap Seconds

michael posted more than 11 years ago | from the stuff-you-thought-you'd-never-think-about dept.

Science 429

@10u8 writes "Since 1972 precision clocks around the world have ticked using atomic seconds, but earth rotation is slowing down. Leap seconds have been inserted in order to keep noon happening at noon, but they upset some timekeepers. Recent discussions have considered discontinuing leap seconds in UTC, and a colloquium in Torino next month will present results. It is a matter of international significance."

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Go get the new GNARKILL CD! (-1)

crow_t_robot (528562) | more than 11 years ago | (#5762540)

GNARKILL r00lz, motherfux0rs!
suck it!

fp (-1)

Anonymous Coward | more than 11 years ago | (#5762542)

First post!!!!!!!

fp (-1, Offtopic)

dkarney (243740) | more than 11 years ago | (#5762543)

And I just bought a new watch! Damn.

Re:fp (-1, Flamebait)

Anonymous Coward | more than 11 years ago | (#5762591)


Yousa watch no good underwater. Not be-sa working in Gungan City. Bee-yotch.

Ouch. You've been trolled by Jar-Jar.

Who cares? (-1)

Anonymous Coward | more than 11 years ago | (#5762544)

Who cares?

4th post (-1, Offtopic)

Anonymous Coward | more than 11 years ago | (#5762545)


TIME BANDITS!!!!

Why? (4, Interesting)

k-0s (237787) | more than 11 years ago | (#5762546)

I can't see why they hate leap second. I'll be damned if I am going to eat lunch at what is called 8:00 in the morning because they don't want to keep leap second. Grow up, we have leap years and human time keeping is not an exact science as the Earth tends to spin the way IT wants not the way we want.

Re:Why? (1, Informative)

Anonymous Coward | more than 11 years ago | (#5762566)

I don't think that is accurate. the concept of leap years is because the roman calendar sucks. The aztecs had a calendar that is much more precise, so did the Incas. The idea that time ticks at a constant rate is stupid anyways. Did relativity teach us that lesson already?

Re:Re:Why? (1)

f00zbll (526151) | more than 11 years ago | (#5762588)

You're wrong. the most accurate calendar is the 13 Moon Calendar created by the Mayan.

Re:Re:Why? (1)

foog (6321) | more than 11 years ago | (#5762613)

I bet neither of you can explain the difference between "precision" and "accuracy", much less intelligently compare the tradeoffs in design between UTC and the old Central American calendars.

Re:Re:Why? (1, Informative)

Anonymous Coward | more than 11 years ago | (#5762627)

Precision: the `depth` to which something is measureed. Ie 1.01023921203 is more `precisely defined` than 1.01024.
Accuracy is what it sounds like - the amount of error in a given reading.

Next?

Re:Re:Why? (1)

foog (6321) | more than 11 years ago | (#5762669)

ok, try this:

intelligently compare the tradeoffs in design between UTC and the old Central American calendars

Re:Re:Why? (1)

stefanlasiewski (63134) | more than 11 years ago | (#5762628)

13 Moon Calendar created by the Mayan.

Is that much different then the 13 Moon Calendars created by every other ancient civilization?

Re:Why? (4, Informative)

Jason1729 (561790) | more than 11 years ago | (#5762632)

The problem with leap days has nothing to do with the Roman calendar. It is because the time it takes the Earth to revolve around the Sun is not an integer multiple of the time it takes the Earth to rotate on its axis. The Lunar calendars you mention have leap-months.

Jason
ProfQuotes [profquotes.com]

Re:Why? (4, Insightful)

Waffle Iron (339739) | more than 11 years ago | (#5762686)

I don't think that is accurate. the concept of leap years is because the roman calendar sucks.

The concept of leap years is because the ratio of the length of a year divided by the length of an earth day is not an iteger. No calendar can get around that fact. You either add intercalation days whenever the remainders of your divisions exceed 1, or you keep track of huge numbers and cycles that greatly complicate your timekeeping.

The Julian roman calendar did suck because they didn't get the ratios quite right and it drifted. (The Gregorian calendar fixed this for all practical purposes.) However, prior to Julius Caesar, it sucked even more because there was no mathematical formula. Instead, priests were supposed to observe the sun each year and decide when leap days were needed.

The priests were also involved in politics, so they chose to shorten political terms more often than not by omitting leap days. IIRC, by the time the Julian calendar was instituted, the Romans were off by several months due to these partisan shenanigans.

Re:Why? (2, Informative)

foog (6321) | more than 11 years ago | (#5762721)

time "ticks" at a constant rate in any particular reference frame (SR), which is how time standards are defined, anyway.

Satellite clocks have to be relativistically corrected, especially for applications like GPS.

Re:Why? (1)

PerlGuru (115222) | more than 11 years ago | (#5762582)

I would agree with you on that one. The information on the site isn't extremeley easy to comprehend but I don't see what the problem with having them is. Towards the bottom there is a link with someones view that having more leap seconds might make the system work better.

Perhaps the problem is that with the leap seconds being inserted basically whenever the people desire it isn't regular and therefore easily predictable so it makes it difficult to properly propogate the decesion to insert a leap second to everywhere that needs to know in advance. Like I said I don't totaly understand all of the info on the page perhaps someone in the know can fill us in.

Re:Why? (1, Interesting)

joe_bruin (266648) | more than 11 years ago | (#5762647)

the trains are now running on time -- metric time.

Accuracy isn't everything... (5, Insightful)

stefanlasiewski (63134) | more than 11 years ago | (#5762655)

And just think, if no leap seconds were added since 1972, you'd be having your Noon Lunch at 11:59:38 [nist.gov] !

Oh the horror... :)

Accuracy isn't everything...

Re:Why? (2, Funny)

aztektum (170569) | more than 11 years ago | (#5762715)

I don't get why being that anal about time keeping is so important anyway. I guess with all the high dollar electronic transactions that go on these days there and what not, but for the average chump going about day to day... if the sun is in the sky it's day time, if it's not, it's night. If it looks like it's in the middle of the sky it's time for lunch.

What's the big deal? Can someone enlighten me?

How cool a job is "Timekeeper"? (2, Funny)

Anonymous Coward | more than 11 years ago | (#5762548)

"So, what do you do?"

"I am a keeper of the time."

Re:How cool a job is "Timekeeper"? (5, Funny)

Znonymous Coward (615009) | more than 11 years ago | (#5762671)

Hi Time Keeper, I'm am the Gate Keeper... Have you see the Key Master anywhere?

Re:How cool a job is "Timekeeper"? (0)

Anonymous Coward | more than 11 years ago | (#5762755)

A '56 Chevy Bel-Air can kick a '47 Buick Roadmaster's ass any day, at least in the first quarter-mile, that is.

Get rid of 'em (0, Interesting)

dirvish (574948) | more than 11 years ago | (#5762552)

I personally think the should get rid of leap seconds and leap years. I'm down for keeping it real. Day light savings time is annoying and I really don't understand the point.

Re:Get rid of 'em (1)

J1a2o (526745) | more than 11 years ago | (#5762617)

But what is "real"? The leap seconds and leap years are so that our time keeps up with what's the "real."

Re:Get rid of 'em (0)

Anonymous Coward | more than 11 years ago | (#5762635)

Day light savings time is annoying and I really don't understand the point.

Day light saving has nothing to do with leap seconds. Don't mix apples and oranges.

* Leap seconds are corrections to re-synchronise human time scheme with physical time.
* Day light saving is something to save enegry in the dark winter period.
While you hate Day light saving... you don't need to hate those tiny lovely little leap seconds. :)

Re:Get rid of 'em (-1, Offtopic)

Anonymous Coward | more than 11 years ago | (#5762661)

bored modders with points/mods to burn.

whatever

I hope... (5, Funny)

MoonshineKid (615121) | more than 11 years ago | (#5762553)

I hope this means we get an extra second of February every four years. I love February.

Re:I hope... (0)

Anonymous Coward | more than 11 years ago | (#5762644)

I hope this means we get an extra second of February every four years. I love February.

how long someone is born on February 30th? :)

Re:I hope... (0)

Anonymous Coward | more than 11 years ago | (#5762693)

About 22 inches.

Why does this mean anything? (-1, Troll)

voxel (70407) | more than 11 years ago | (#5762554)

Who cares. Why are we bickering over a LEAP-SECOND. Put your energy into more important matters... Seriously.

Re:Why does this mean anything? (5, Funny)

Anonymous Coward | more than 11 years ago | (#5762587)

Who cares. Why are we bickering over a LEAP-SECOND. Put your energy into more important matters... Seriously.

Yeah, let's bicker over whether we should be bickering over leap seconds. Much more productive.

S2B bugs, here we come! (2, Funny)

lightspawn (155347) | more than 11 years ago | (#5762557)

Considering that some programmers (of commercial software, no less) have no idea HOW TO CHECK IF A YEAR IS A LEAR YEAR, I fear this is going to be no less catastrophic than Y2K, perhaps even a cataclysm of Y2038 proportions!

Excuse me while I stock up on food, medicine and ammo.

Re:S2B bugs, here we come! (1, Funny)

Anonymous Coward | more than 11 years ago | (#5762570)


Lear years rock!!!! Also, you are dumb.

Re:S2B bugs, here we come! (3, Funny)

lightspawn (155347) | more than 11 years ago | (#5762636)

1. Sorry about the typo; I apologize.

2. I'm actually rather smart, but sometimes instead of a word's last letter I type the next word's last letter. You may classify it as mild dyslexia; it's mostly not a problem since most people can understand what I meant from context.

3. The person sitting next to me right now has been using excessive amounts of glue for the last few minutes; I'm not sure what its purpose was, but some of you CSI fans can no doubt explain how certain types of industrial-strength glue can cause synapses to misfire.

4. Again, I apologize for any inconveniece. As a token of good will, please accept this coupon, good for ignoring one (1) typo or grammar error in any future slashdot posting. Expires 6/18/2003.

Re:S2B bugs, here we come! (0)

Anonymous Coward | more than 11 years ago | (#5762703)

I second the notion that you are dumb even without the typo. Leap seconds already exist and are inserted when it is determined they are needed. It really is of no concern to programmers since it doesn't require any odd time or date measurements (i.e. Feb 29th). Most networked computer sync to a server which serves to a NTP server somewhere which syncs to the main Naval Observatory timekeeper (or something like that).

Re:S2B bugs, here we come! (1)

PerlGuru (115222) | more than 11 years ago | (#5762624)

oh no!!!! I don't know how to check for a lear year... shoot. I better head to CPAN and see if I can find a module to do it for me before my stuff breaks.

Re:S2B bugs, here we come! (0)

Anonymous Coward | more than 11 years ago | (#5762654)

A good supply of fresh porn might serve ye well, also.

Every four years (1, Funny)

Anonymous Coward | more than 11 years ago | (#5762558)

Februray will lose 1 day and a few seconds. Whats the big deal? Wait slower...that means I have to work longer. NOW THAT SUCKS!!!

the meaning of time (0)

bromoseltzer (23292) | more than 11 years ago | (#5762559)

As a /. contributor, I found it slyly ironic to see this post in red with the caption: "Posting will only be possible in The Mysterious Future!"

-mse

Re:the meaning of time (0, Offtopic)

kingkade (584184) | more than 11 years ago | (#5762745)

i found myself beating my skull in with my own little fists when trying to figure out what "slyly ironic" could mean. i cried for so long, bromo. so long.

WWV (4, Informative)

io333 (574963) | more than 11 years ago | (#5762562)

Everything you ever wanted to know about precise timekeeping, from the keeper himself! [bldrdoc.gov]

a leap what? (0, Troll)

EvilStein (414640) | more than 11 years ago | (#5762564)

"It is a matter of international significance."

It's so important that neither myself nor the 8 slack offs I work with had any clue that "leap seconds" existed.

Can we add some more in? Anything that makes quttin' time get here faster gets my vote.

Re:a leap what? (0)

Anonymous Coward | more than 11 years ago | (#5762603)

The length of the mean solar day has increased by roughly 2 milliseconds since it was exactly 86,400 seconds of atomic time about 1.79 centuries ago (i.e. the 179 year difference between 1999 and 1820). That is, the length of the mean solar day is at present about 86,400.002 seconds instead of exactly 86,400 seconds. Over the course of one year, the difference accumulates to almost one second. Other factors also affect the Earth, some in unpredictable ways, so that it is necessary to monitor the Earth's rotation continuously.

Re:a leap what? (0)

Anonymous Coward | more than 11 years ago | (#5762716)

Ah yes. Importance is to be measured by 9 idiots who probably spend most of their day downloading faked Olsen twin porn.

Here's a clue. There's is probably a lot that goes on in the world that you don't know anything about.

Is it time to change time? (2, Interesting)

Blaine Hilton (626259) | more than 11 years ago | (#5762565)

With the increasing amount of precision in today's timekeepers these problems seem to be cropping up more and more. I don't believe it really matters, except the whole world needs to agree on a standard. With our global economy (weather we like it or not) times need to be synced across the world.

Although if there are going to be changes to the time standards I can always add converters [webcalc.net] to my calculator site for people to use.

Re:Is it time to change time? (1)

jonathanbearak (451601) | more than 11 years ago | (#5762658)

we've been measuring time on the atomic scale for a half century now, i suppose what really needs to be done is to choose a common epoch (or result to using negative relative time). how about the unix epoch? :)

Actual effects (0)

deadpete.tripod.com (597253) | more than 11 years ago | (#5762571)

Okay, so the clocks need to be changed. How does this really effect life on Earth? Would a slowed rotation effect the ecology? has this been long in progress, or more recently?

Saying "the Earth will stop spinning" has always been an idiom for disaster (used for hyperbole), but what will actual happen now that it is happening?

Re:Actual effects (1, Funny)

Anonymous Coward | more than 11 years ago | (#5762602)

Let's just make a law that all planes must take off to the west.

That's great, but Indiana won't participate (5, Funny)

dobedobedew (663137) | more than 11 years ago | (#5762574)

We don't even do Daylight Savings Time here in Indiana. Whatever the rest of the world decides, we will resist - I can't wait to see our citizens and politicians get in an uproar over this!

Re:That's great, but Indiana won't participate (1)

SparkyTWP (556246) | more than 11 years ago | (#5762672)

Yes they do. Lake County observes Daylight Savings with maybe one or two other counties. I should know, I grew up there :P

Re:That's great, but Indiana won't participate (4, Funny)

tap (18562) | more than 11 years ago | (#5762725)

Actually, you do use daylight savings time in Indiana [mccsc.edu] . There are eleven counties that are on central time and use DST, five counties that are eastern time and use DST and 76 counties that are eastern time and don't use DST. So Indiana has no less than three different time zones. At least they don't have multiple timezones per county.

Given Indiana's history with keeping time, probably half the counties will participate and half won't. And some will just switch to the Mayan calander and be done with it.

which came first? (0)

Anonymous Coward | more than 11 years ago | (#5762577)

Yup, leave it to the engineers to tell the Earth that's its clock is off. Surely there's a group of guys at ISO trying to figure out how to speed up the Earth so it matches our clocks! ;)

No leaps needed... (1)

i.r.id10t (595143) | more than 11 years ago | (#5762585)

... except maybe keeping Feb 29 around, just for old times sakes.

What will be required to make that really work though will be a change of mindset over the years - but we probably won't be around to see it happen. In a few millenia when noon has actually shifted to what could be today's quarter 'til 10, they will hopefully have a different concept of morning/first daylight at somewhere between 6 and 8 (or whatever it is... I'm never awake that early.)

Re:No leaps needed... (1, Funny)

Anonymous Coward | more than 11 years ago | (#5762608)

You better keep Feb 29th, I don't wanna die at the age of 6!

Re:No leaps needed... (1)

skillet-thief (622320) | more than 11 years ago | (#5762729)

In a few millenia when noon has actually shifted to what could be today's quarter 'til 10, they will hopefully have a different concept of morning/first daylight at somewhere between 6 and 8

People, in general, don't seem to give much of a damn about when noon happens. They would prefer noon to happen at 6 in the afternoon if they don't have to change their watch too often when they travel to the next town.

In Europe, it can really be strange. Except for the UK (and possibly Ireland, don't remember), it is all one timezone from Berlin to Lisbon. Basically, it is the correct TZ for Germany, which means that in Portugal you are probably around 2 hours off.

In the winter.

But in the summer, everybody switches to daylight savings, so they are another hour off. Apparently nobody seems to complain, though. Personally, it seems wrong somehow though.

Obligitary Hitch Hiker quote (4, Funny)

Zerbey (15536) | more than 11 years ago | (#5762596)

Time is an Illusion. Lunchtime doubly so.

Re:Obligitary Hitch Hiker quote (1)

Fenis-Wolf (239374) | more than 11 years ago | (#5762629)

Gotta love Hitch Hiker stuff :-)

All this bickering about UTC and leap seconds... (-1)

SLASHDOT EDlTOR (589794) | more than 11 years ago | (#5762598)

it is all relative.

Time measuerments that make sence... (5, Funny)

Eric_Cartman_South_P (594330) | more than 11 years ago | (#5762599)

I've said this before, but I think Maxtor Hard Drive MTBF rates and Iomega tape drive MTBF rates are good, consistent, short time measuerments (both very shitty products that fail reliably).

Me: Wanna go have sex?
Hot Girl: OK! When?
Me: I'm on lunch break in 3 Maxtors and a Tape.
Hot Girl: I'll pay for the Hotel room.

Re:Time measuerments that make sence... (0)

Anonymous Coward | more than 11 years ago | (#5762700)

You are quite possibly the biggest loser to ever post on slashdot.

The comment is inane and not humorous at all.

Please kill yourself.

This doesn't make any sense at all (2, Funny)

rrkap (634128) | more than 11 years ago | (#5762701)

A slashdot reader having sex with a hot girl????????

Either the poster's definition of hot, girl or sex is seriously out of whack.

Re:Time measuerments that make sence... (0)

Anonymous Coward | more than 11 years ago | (#5762765)

dude, that is not funny. shut up

For Those Interested About Leap Seconds In General (5, Informative)

PipianJ (574459) | more than 11 years ago | (#5762604)

This site [navy.mil] may be more helpful, especially in clearing up some of the problems with leap seconds (and their ultimate creation of an offset from both TAI and GPS time)

Re:For Those Interested About Leap Seconds In Gene (1)

PerlGuru (115222) | more than 11 years ago | (#5762643)

Thanks, that site is great and very readable/understandable. I definatley think you deserve a 5 - informative

Re:For Those Interested About Leap Seconds In Gene (0)

Anonymous Coward | more than 11 years ago | (#5762768)

Your post on the other hand, is not very readable/understandable. Let me put it in terms you may understand:

s/definatley/definitely/

Loser.

stop reading these stupid articles (-1, Offtopic)

Anonymous Coward | more than 11 years ago | (#5762607)

and go download the new animatrix!

beep beep boop!

Re:stop reading these stupid articles (-1, Offtopic)

Anonymous Coward | more than 11 years ago | (#5762728)

hehehe!! beep beep boop!! hehe beep beep boop i like that. have fun with the new animatrix buddy

From The-You-Are-Very-Right Dept. (0, Redundant)

miketang16 (585602) | more than 11 years ago | (#5762610)

stuff-you-thought-you'd-never-think-about dept.

I don't like to think about leap years, much less leap seconds...

The easiest solution to all this is (4, Funny)

happyhippy (526970) | more than 11 years ago | (#5762615)

SPEED UP THE EARTH!

I propose we keep the earth spinning at a constant rate by detonating thousands of nukes at certain places once every four years. This will produce a Catherine Wheel effect and the earth will speed back to its original spin rate.

I am going to patent this idea but I fear itll be 500 years before I get it processed.

Re:The easiest solution to all this is (1, Funny)

Anonymous Coward | more than 11 years ago | (#5762634)

Just have everyone run west at the same time for a while on the whole planet. Duh!

Re:The easiest solution to all this is (1)

happyhippy (526970) | more than 11 years ago | (#5762641)

Dont be stupid.

Re:The easiest solution to all this is (1)

unicron (20286) | more than 11 years ago | (#5762657)

Yeah, seriously. I don't run.

Re:The easiest solution to all this is (0)

Anonymous Coward | more than 11 years ago | (#5762776)

I hear ya fatty. Maybe if you just jumped up and down a few times it would fix the rotation problem. You'd probably burn 2000 calories while you were at it too.

Re:The easiest solution to all this is (1)

the Atomic Rabbit (200041) | more than 11 years ago | (#5762684)

That violates angular momentum conservation.

Re:The easiest solution to all this is (1)

squidfood (149212) | more than 11 years ago | (#5762722)

That violates angular momentum conservation.

Why? Energy released from nukes can change angular momentum. The only problem is directing the nukes (doing at ground level = pushing the air attached to the earth = friction). You'd have to attach the nukes to long poles sticking up into vacuum.

You're too young... (1)

NineNine (235196) | more than 11 years ago | (#5762757)

You're obviously too young... if you were at least, say, 30, then you'd know that Superman can do this all by himself. No need for nukes. Jeez, kids these days...

Changing the way we keep time... (1)

pergamon (4359) | more than 11 years ago | (#5762618)

... yeah, there won't be any problems with that.

Leap second: history and possible future (3, Informative)

PickaBooga (578529) | more than 11 years ago | (#5762622)


This is the link to a summary of the issues involved, written at a slightly less technical level.

(don't have to pay, don't have to register, etc.)


http://www.cl.cam.ac.uk/~mgk25/c-time/metrologia-l eapsecond. pdf

"It is a matter of international significance"... (-1, Flamebait)

jbum (121617) | more than 11 years ago | (#5762623)

TO THE ANAL-RETENTIVE.

an attempt at a summary.... (5, Informative)

Malor (3658) | more than 11 years ago | (#5762630)

If I understand what I read correctly, essentially the problem they're trying to solve is this: the Earth's rotation is slowing, but they can't predict exactly how much it's going to slow at any given time. It is a real, physical thing, and while they can model its orbit with extreme and unchanging accuracy (things are widely separated enough that the mathematical abstractions work fine), modeling its rotation isn't really possible. There's all sorts of liquid sloshing around everywhere, both liquid water on the surface and molten rock in the center. All they can do is measure it, and every once in awhile, determine that sunrise is happening just a little late.

There are two major timekeeping systems: TAI, which is "absolute time" and is never adjusted, and UTC, which is "civilian time". Because UTC is used by normal people, they try to keep it synced to the Earth's rotation, which in theory at least makes it more useful for us mere mortals. (knowing that the sun will rise at exactly X time on X date at sea level, for instance.). So, gradually, UTC diverges from TAI, because one rotation of the Earth is just a little longer than 24 hours, and over time this divergence adds up to be greater than a second. When it's getting close, they add a leap second. These additions are not at regular intervals, because they can't predict exactly when any given second should be added.

There are occasional problems when they add the leap seconds (programs that don't expect 61 seconds in a minute, for example), or programs that don't realize that there are X number of seconds (15 or so?) that simply didn't exist since 1970. (sometimes this stuff matters).

Thus, they're debating about doing away with leap seconds altogether. One possible substitute is a 'leap hour' every thousand years.

It seems like a rather anal-retentive thing to argue about, but these people are paid to be precise to a degree we can't even imagine.

A worthy slashdot story. This is serious geekery. :-)

Re:an attempt at a summary.... (4, Funny)

Tackhead (54550) | more than 11 years ago | (#5762711)

> Thus, they're debating about doing away with leap seconds altogether. One possible substitute is a 'leap hour' every thousand years.

Why not?

Asshats from the Industrial Revolution days make us do a frickin' "leap hour" twice a year anyways, one of which violates causality. Fuckin' Daylight Savings Time.

What drooling asshat decided that it'd be a good idea if, every year, there was one day when everyone's heart/respiration rates slowed down to one beat/breath per hour, and about six months later, these same people should be able to start a 20 minute download that finishes 40 minutes before it started?

Fine if you've got a black hole nearby for the former, and fine if you can travel faster than light for the latter.

The day we have those technologies, fine. Until then, no, no, no, no, no, these are bad, bad, bad, bad, bad ideas.

Why is earth's rotation slowing down ? (0, Offtopic)

zymano (581466) | more than 11 years ago | (#5762638)

Too many people farting in one direction.

precision timekeeping is real interesting stuff (5, Insightful)

foog (6321) | more than 11 years ago | (#5762648)

And why do we care?

Read the article!

It's important for systems programmers, and lots of folks here are at least systems programming fanboys.

It's important for navigation. Yeah, that includes your GPS toys.

It's important for a number of scientific disciplines, including a number of subdisciplines of radio astronomy.

It's also really interesting that the change in the Earth's rotation can't yet be predicted with enough accuracy to set a schedule in advance for adding leap seconds, but must be measured. This is relatively prosaic stuff that's nonetheless at the limits of our current understanding. Doesn't anyone get excited or curious about science anymore?

It will take a while before we notice (1)

SourceHammer (638338) | more than 11 years ago | (#5762651)

at around 4 1000th's of a degree for each leap second, it will take a while before it makes any difference; my sundial will be ok.

We should set our clocks based on the rate that the universe is rotating instead.

Re:It will take a while before we notice (1)

jonathanbearak (451601) | more than 11 years ago | (#5762677)

"We should set our clocks based on the rate that the universe is rotating instead."

yeah, i just checked nasa's latest theory on that, it's so accurate i'm sure that number will *never* change!

So what will they do? (1)

bazmonkey (555276) | more than 11 years ago | (#5762652)

Since I find it hard to believe that they're actually going to let our time degrade to the point that noon happens when the clock says 2am of the next day, what exactly do they propose we do? Will UTC be different from the time we'll all use? That way, UTC can be weirdly off, but ours will be ok.

If keeping our noon time happening when noon happens is a priority, I can't think of an easier way to do it than leap seconds.

We should just go back to sun time... (1)

anthony_dipierro (543308) | more than 11 years ago | (#5762653)

Then high noon is always high noon.

Leap seconds and leap years, keep em (2, Interesting)

zarthrag (650912) | more than 11 years ago | (#5762662)

first of all, I think it's important to keep on track with time, it's not like we don't have the technology to keep it up. Isn't it amazing that we can even develop the concepts in the first place? Leap years have been incorporated for awhile now, it keeps the seasons from drifting to some "other" part of the calendar. (Winter in July anyone?) Daylight savings wasn't invented to annoy people or make people appreciate the season by forcing you to be awake earlier. It saves energy by having people awake during the daylight hours. This means you're more likely to open a window than cut on a light, and go to bed while it's dark out. While leap seconds are comparatively minute, it's just maintence. (Y2k is an example of what happens when we don't think far enough ahead). I think modern-day timekeeping is the result of centuries of work. It started with us observing the sun, then the stars, and now the earth itself. Needless to say, timekeeping ought to be an exact science. Until we find something more reliable of deserving to serve as a time reference, we ought to keep our ears to the ground. We do happen to live here, and I think the Earth deserves to set the pace.

Re:Leap seconds and leap years, keep em (1)

rev063 (591509) | more than 11 years ago | (#5762706)

(Winter in July anyone?)

Why not? Those that live on 50% of the Earth's surface seem to cope with Winter in July just fine!

Pet peeve: software companies that announce their next product will be launched in the Spring. Now, within 6 months, when is that please?

Instead (1)

soorma_bhopali (643472) | more than 11 years ago | (#5762668)

try to realize the thruth ...

What truth?

There are no leap seconds ....

coding for leap-seconds (2, Informative)

Anonymous Coward | more than 11 years ago | (#5762675)

requires a lookup table and regular (like every
two weeks) network connections to the Navy's
leap second table server to detect updates,
and the software needs to parse the table and
account for the update if and when it occurs.

Since we have not had a leap second update since
1999, it has meant there has been lots of time
for folks to get complacent and ignore the update
checks, so most recent code that handles leap
seconds is trouble waiting to happen.

I will be very happy when leap seconds are put
to bed.

leap seconds are evil (1, Interesting)

imp (7585) | more than 11 years ago | (#5762688)

Leap seconds are evil. As someone who has spent way too many hours programming high precision time distribution systems to deal with leap seconds, I'd say 'good riddance, don't let the door hit you on the way out. Sites that have to deal with them typically shut down near leap seconds to avoid any glitches. The amount of time wasted on this problem boggles the mind.

I hate them and will not morn their passing.

It's not a hude deal. (0, Offtopic)

Znonymous Coward (615009) | more than 11 years ago | (#5762694)

Everyone is always saying "There aren't enough hours in a day". If the Earth is slowing down, we can just add more hours to the day to make up for it. Think of all the lives we will be improving. I mean, I could jack off at least 26 times in a 26 hour day. Yes!

What are leap seconds? (5, Interesting)

Phroggy (441) | more than 11 years ago | (#5762698)

Leap years work like this:

One year = the time it takes for the Earth to revolve around the Sun.
One day = the time it takes for the Earth to rotate on its axis.

The problem is, there are really about 365-1/4 days in a year - it doesn't work out evenly to 365 days. So, every four years we add an extra day (Feb. 29), and then it all averages out. Otherwise, if we only had 365 days in a year, over many years seasons would start getting earlier and earlier on the calendar.

One day = the time it takes for the Earth to rotate on its axis
One second = the time it takes for Cesium 133 to oscilate about 9.19 billion times (because it's something constant we can measure)

The problem, again, is that there aren't exactly 86400* seconds in a day. So, we add leap seconds periodically to account for it. As I understand it, this isn't necessarily done at fixed intervals, but rather whenever it's decided that it needs to be done. The Network Time Protocol used to synchronize clocks over the Internet supports leap seconds; they can be announced over NTP in advance, so everybody adds them at the correct moment.

Why is it important? It's not important to most people, but computers like things to be precise and accurate for various reasons, and that means we have to agree on exactly what time it is.

* BIND now lets you write "1d" in a zone file, but how many of you still have this number memorized? ;-)

I bet it was France... (1, Funny)

Anonymous Coward | more than 11 years ago | (#5762718)

They vetoed the leap second, didn't they?

Seconds anyone? (1)

confused philosopher (666299) | more than 11 years ago | (#5762738)

I'm confused, as usual.

Does anyone know or care what second the WTC disaster, or Pearl Harbour, or Moon Landing happened at? No. Days matter for history and calculations, seconds do not.

There is nothing significant enough to deserve an exact keeping of seconds, when humanity won't span long enough to have those extra seconds turn into days.

Time zones (5, Insightful)

cperciva (102828) | more than 11 years ago | (#5762742)

The stated problem with leap seconds is that some software gets confused by them. Guess what? That same software probably gets confused if the time zone changes, or when it moves into daylight savings time.

The Right Way to solve this problem is for computers to work with TAI internally, and treat the difference introduced by leap seconds as part of the time zone, for human consumption only. Instead of defining PST to be UTC - 08:00, define PST = TAI - 08:00:22.

Computers can keep their straightforward time system, humans can keep our astronomically synchronized system. No need to lose either of those qualities.

Significant!? (0)

Anonymous Coward | more than 11 years ago | (#5762761)

"It is a matter of international significance"

I'm gonna have to call bullshit here.

Ya'll think it's confusing now? (1)

NanoGator (522640) | more than 11 years ago | (#5762769)

Just wait until the galactic standard week goes into effect.
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