Year 2005 Extended by One Leap Second Scientists have extended 2005 by one second. A leap second will be added on Dec. 31, the first one since 1998.
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Year 2005 Extended by One Leap Second

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Year 2005 Extended by One Leap Second

Year 2005 Extended by One Leap Second

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  • <iframe src="" width="100%" height="290" frameborder="0" scrolling="no" title="NPR embedded audio player">
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If you're sad to say goodbye to 2005, take comfort in the fact that you'll have one extra second to enjoy it. We've all heard of leap years, but this Saturday scientists are adding a leap second to atomic clocks around the Earth. It's the first time since 1998 we've made an adjustment to our world clock, known as Coordinated Universal Time. What will you do with your extra second? Give us a call at 1 (800) 989-TALK, or send us an e-mail at

To explain all this, we're joined in Studio 3A by Jeff Chester, an astronomer at the US Naval Observatory.


Mr. JEFF CHESTER (Astronomer, US Naval Observatory): Thank you. Glad to be here.

SEABROOK: Why do we have to add a second to this year?

Mr. CHESTER: Well, this all started with those pesky astronomers. We've been kind of on the surface of the Earth for, oh, a few thousand years calmly watching the stars and that sort of thing. Somewhere along the line somebody thought, `Gee, we ought to be able to record when we see things happen in the sky.' So they began to look for natural rhythms that would allow them to develop time scales. So things like the rising and the setting of the sun, the coming and the going of the moon, the waxing and waning of the seasons--these all became the things that today we kind of take for granted as days, months, years and so on.

Basically, all of these time systems are dependent on what the Earth is doing as opposed to what a sort of neutral arbiter might say. And the problem is physicists sooner or later came along, and physicists don't like defining things that are fundamental physical constants in terms of systems that are inherently variable. So they said, `OK, we have to find a better way to define this thing called the second.' And eventually they hit on the idea of using a natural vibration in a particular kind of chemical element that oscillates about nine billion and change times per second, and they use that to define the duration of the second. And...

SEABROOK: Which element?

Mr. CHESTER: It--well, the formal definition of one second is the duration of 9,192,631,770 cycles of the hyperfine state of cesium-133 in a vacuum in the absence of external magnetic fields.

SEABROOK: I'll keep that in mind.

Mr. CHESTER: Good, 'cause it takes a lot longer to say it than it does to actually make the thing go by.

SEABROOK: It's a lot longer than a second, yeah.

Mr. CHESTER: That's right. But the physicists had their sort of--they were happy with that definition of the second. The astronomers were perfectly happy going on with the second that was defined by the rotation of the Earth. Somewhere along the line somebody had to kind of get the two sides together and sort of make them play nice together. So in 1972, an international conference was convened, and it was decided that rather than try to knock everybody's heads together and make them agree on one time scale, that they would actually have two parallel time scales, each based on atomic time. But the one that we use for civil timing purposes and that sort of thing, which is Coordinated Universal Time, would essentially mirror what the Earth is doing. It would be a time scale based on the atomic second, which is constant, but it would be adjusted periodically for the gradual slowing in the rotation rate of the Earth.

SEABROOK: So that's what we're doing?

Mr. CHESTER: That's basically what we're doing. In essence, what we're doing is we are stopping the atomic clocks around the world for one second to let the Earth catch up because, when you think about it, it's a lot easier to do it that way than it is to, you know, get Superman out of retirement and have him come do his thing on the Earth itself.

SEABROOK: Quickly, Jeff Chester, give me an idea of who cares about this. I mean, air traffic control, power grids--who cares?

Mr. CHESTER: Air traffic control, power grids. In 1972--we have to kind of jump back in the time machine and put ourselves back, those of us that can remember it--put ourselves back in that situation, where if somebody had told you that there was going to be a computer on your desktop that would literally be networked to computers everywhere around the world, you would have said, `Ha! Yeah, right.' That's the case. We have to synchronize everything today very precisely in order to make everything talk to each other. So global positioning system satellites, we have an error of one second, that's an error that's two-thirds of the distance to the moon.


Mr. CHESTER: That's a big error.

SEABROOK: Jeff Chester is an astronomer at the US Naval Observatory. He joined us here in Studio 3A.

Thanks so much.

Mr. CHESTER: You're very welcome.

SEABROOK: Let's get to some of our calls. We've been asking people what exactly are they going to do with their extra second.

Chuck in Wisconsin, what are you going to do?

CHUCK (Caller): Hello?

SEABROOK: Hi, Chuck. What are you going to do with your second?

CHUCK: Well, actually I thought about it a little bit. I can't imagine anything better than just to give my wife a kiss right at that precise moment.

SEABROOK: Ohh. Thanks, Chuck. Dave in Salt Lake City?

DAVE (Caller): Yes. I am very excited about this because it's going to give me a chance to work on a neglected item on my to-do list.

SEABROOK: Which is?

DAVE: Write a novel.

SEABROOK: Oh. Good luck.

DAVE: Thank you.

SEABROOK: Good luck with that, Dave. Nathan in Hot Springs, Arkansas, what are you going to do?

NATHAN (Caller): Well, I'm going to take some time off, maybe ponder the year.

SEABROOK: Oh, that's nice. OK. That's a good thing for all of us to do.

We also got a few e-mails in. Glen in Boise, Idaho, said he would take an extra second to rest before charging into the new year. Jerry in Cleveland, Ohio, also said that he would use the extra second to kiss his wife--a lot of husbands out there doing good things. And, also, we have somebody--Eric in San Francisco, also says he plans to write and finish his novel.

You're listening to TALK OF THE NATION from NPR News.

And you may not know this. Before we introduce this next guest, I want to explain something about how we work here at NPR. I'm sitting in a studio. I'm looking around me, and I literally see five clocks. These are five clocks that are all linked to each other. They're counting down time to the end of this segment. And every single clock is actually adjusted with clocks and synced with clocks at every single member station across the country and beyond, over 600 member stations.

To us, adding a second is big business. If we don't, we call that busting the clock. I could run over, and, boy, I'd have a lot of angry stations on the phone with me. Big business here. Toby Pirro is the STC supervisor here at NPR. STC means System Technical Center. For three months he's been getting ready for the leap second, and he joins us now. Thanks, Toby.

TOBY PIRRO (STC Supervisor, NPR): Good afternoon.

SEABROOK: Tell us the scope of this challenge. I mean, we're talking about the clocks here, not just at 635...


SEABROOK: ...(unintelligible)--not just here at 635 Massachusetts Avenue Northwest; I mean, around the country.

PIRRO: We tie in across the satellite--along with their program signal, we have a data signal that keeps their local clocks in sync with the network. So, as you said, when you are making your announcements, you want to hit the post, so they know when you're going to stop, so they know when they can do what they do.

SEABROOK: When will NPR add the second?

PIRRO: We're cheating a little. The actual scheduled time is at 7 PM on Saturday evening Eastern time. And we will let the stations get into their 7:00 programs, get through the newscast, and then actually at 7:15 PM is when we are going to make the adjustment that the stations will see in their automation systems.

SEABROOK: Now the reason why it happens at 7 is because that's when Greenwich Mean Time does it?

PIRRO: That is midnight. That is when January 1 starts, where they start counting.


PIRRO: And instead of doing it hour by hour, as they do in the spring and the fall, when you do the spring forward-fall back, they just decided to just do it everywhere around the world all at once for that one second.

SEABROOK: So actually our NPR listeners get a whole second more of radio.

PIRRO: Or not.

(Soundbite of laughter)

SEABROOK: And as a reporter, if I'm reporting on the shows, my story could be a second longer.

PIRRO: We've actually talked with the people working on the New Year's Eve programming, and for that hour they're already contemplating filling that extra second with programming. So they take it very seriously. We all take it very seriously.

SEABROOK: More fund-raising. Hey!

PIRRO: Exactly.

SEABROOK: That's what our listeners love. Toby, how difficult was it, really? Why did it take you three months to work out how to do this?

PIRRO: We have a lot of different parts of the company, divisions. We've got the people who do the announcing. We have the people that do producing of the news. We have our engineering department, the people that take care of the equipment. Everyone wanted to be in touch with everyone to know that it was happening. Of course, it's on Saturday night, it's on the holiday night. We just want to make sure it's in everybody's radar that this was going to be happening and either that there are people in place to do it or that the equipment was ready to perform. We have a master clock system that we are going to program to take care of the switch and just want to give everybody a head's up that has a piece of it.

SEABROOK: We have a couple callers on the line with interesting questions. Matt in San Jose, how are you?

MATT (Caller): I'm doing well. Yourselves?

SEABROOK: Good. How about that second? What are you going to do?

MATT: Well, I'm actually going to spend it contemplating how much of the other software I've written in my career is going to properly account for that.


MATT: Well, every UNIX-based system--and, believe it or not, that's not just computers these days; that's everything up to and including those little digital records...

SEABROOK: Yeah. Toby, does NPR have to worry about that as well?

PIRRO: Actually that's, in part, why we're taking--we'll actually take our clocks--our automation off the clock system, let it play through the top of the hour, then play catch-up. So we've taken that into account.

SEABROOK: John in Cincinnati, what are you going to do with the second?

JOHN (Caller): Hi. I hear the interest rates are going to go through the roof again. It's a rumor maybe. But I thought if I could invest the second for about 20 or 30 years and reap the benefits of the investment later...

SEABROOK: Good luck, John. Work on that.

Toby Pirro, we've got a couple more e-mails from listeners. Andy says that there's something a little sad about having it. He wants to watch his computer switch over as the extra second appears. Rea(ph) in Starbuck, Washington, says that she's going to use the extra second to swallow more champagne. And Kim says it's a moment to pop another piece of chocolate into her mouth.

Toby Pirro of STC and here at NPR, thanks so much.

PIRRO: Thank you.

SEABROOK: From all of us at TALK OF THE NATION, have a happy New Year. Neal Conan will be back on Monday. I'm Andrea Seabrook.

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