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Science Technology

New US Atomic Clock Goes Live 127

Posted by samzenpus from the in-real-time dept.
PaisteUser (810863) writes with news about a new, hyper-accurate atomic clock unveiled by the National Institute of Standards and Technology. "A new atomic clock, so accurate it will lose or gain only one second every 300 million years, was unveiled Thursday by the National Institute of Standards and Technology, a branch of the U.S. Department of Commerce. The NIST-F2 had been in development for about a decade and is three times more accurate than the F1, which has been in use since 1999. The institute will continue operating both clocks for now at its campus in Boulder, Colorado."
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New US Atomic Clock Goes Live More

New US Atomic Clock Goes Live

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  • Ah another seemingly benign NIST approved standard (Score:4, Funny)

    by bazmail ( 764941 ) on Thursday April 03, 2014 @06:42PM (#46655211)
    I wonder what backdoor the NSA has built into this.

  • What do we have to reference it against, and isn't it arbitrarily exactly correct?

    How the hell would we know if it was wrong?

    • Re: (Score:2)

      by Kenja ( 541830 )
      It is the reference. Time is relative, we use these atomic clocks to set standards for comparison.

      • Exactly, this will be the standard for all other time standards. Just like they have their standard kilogram stored in a vault in france for reference: http://www.wired.com/2013/01/k... [wired.com]

        • Re:Mod parent up (Score:4, Informative)

          by alexander_686 ( 957440 ) on Thursday April 03, 2014 @07:09PM (#46655581)

          No, the weight of a kilogram is completely arbitrary. They are trying to fix it to something but right now it is just a weight.

          A atomic clock works by counting the vibrations in an atom. The atomic clock fails when it miscounts the vibration of an atom, causing the error. The new clock is so good at counting that errors rarely occur.

          • They are trying to fix it to something but right now it is just a weight.

            Kilograms are a weight.

          • Re: (Score:2)

            by msauve ( 701917 )
            Kilograms are units of mass, not weight ( that would be Newtons, which is a force).

            Errors are not caused by "miscounting," but due to the fact that no physical realization can be perfect. The second is defined under the conditions of zero acceleration (i.e. no gravity) and at a temperature of absolute zero, neither of which are attainable in practice.

        • Re: (Score:3)

          by msauve ( 701917 )
          The internationally agreed time standard (TAI or UTC, which are the same, only different) is based on an ensemble of clocks throughout the world. The contribution from NIST (and USNO) is only a part of the realization.

          Because of this, actual time can only be known after the fact, because post-processing is needed.

      • Re: (Score:3)

        by bazmail ( 764941 )
        If it is the reference then making claims about its accuracy is surly redundant?

        • Re: (Score:1)

          by Anonymous Coward

          I dunno, it rather seemed politely redundant to me. Not threatening at all.

          • Sadly, AC or not, I would have modded this up if only my mod points hadn't disappeared today.

            rgb (and don't call me Surly...)

        • Re: (Score:1)

          by Anonymous Coward

          The accuracy referred to is the measurement uncertainty of the instrument. Imagine you built ten of these clocks, and put them in adjacent rooms. The accuracy can be considered to be the mean drift between the clocks over time.

          This is an over-simplification, because it is infact measured by comparing the clock to other atomic clocks distributed across the world, each of which is adjusted by taking known relativistic effects and other biases into consideration, and they are non-linearly averaged to create UT

        • Re: (Score:2)

          by AmiMoJo ( 196126 ) *

          Atomic clocks work by counting the vibrations of atoms. We can determine how good the clock is at counting the vibrations, and from that calculate how much error it will see over time. It's done with statistics, i.e. how likely the clock is to miss a vibration.

      • And what, exactly, is the point if they have to reset it every year or two anyway due to leap seconds?

        • Not sure if the parent is simply being funny, but ...
          No atomic clock is ever 'reset' because of leap seconds. All they produce is a one-pulse-per-second 'tick'. The labels on those ticks are completely arbitrary. When a leap second occurs, you just change the labels ...

    • I guess it's "good enough for government work".

    • Re: (Score:3, Funny)

      by grub ( 11606 )
      Every day at noon they compare it to the sundial out back.

    • Re:How, exactly, do we know? (Score:4, Interesting)

      by schneidafunk ( 795759 ) on Thursday April 03, 2014 @07:11PM (#46655607)

      Even if it is arbitrary, we can use it for synchronization as long as every relies on it as the standard.

      FTA:
        "If we've learned anything in the last 60 years of building atomic clocks, we've learned that every time we build a better clock, somebody comes up with a use for it that you couldn't have foreseen," says physicist Steven Jefferts, lead designer of NIST-F2.

    • It is, actually, possible to measure such things.

      Consider GPS, which relies on the accuracy of atomic clocks in orbit. Each GPS satellite has its own independent clock, which must be accurate to within about 40 billionths of a second, over the life of the satellite. http://gpsinformation.net/main... [gpsinformation.net] If the accuracy of one of the satellites' clocks is greater than that threshold, your GPS unit will incorrectly report your location. The accuracy of GPS coordinates is one way to calculate the accuracy of t

    • At least, every timekeeping instrument I've ever heard of is designed to measure fractions of the interval defined as a day/year/trip around the galactic center (at this point, I'm considering the calendar to be an extension of the clock).

  • So... (Score:3, Insightful)

    by minipulator ( 821212 ) on Thursday April 03, 2014 @07:00PM (#46655437)
    How do I point ntpdate to it?

    • Re: (Score:2)

      by HunterZ ( 20035 )

      I want to know that same thing, but for the cluster of ntpd servers running on my LAN.

      • I want to know that same thing, but for the cluster of ntpd servers running on my LAN.

        I'd help you but you didn't specify you were running a Beowulf cluster.

    • Re: (Score:2)

      by msauve ( 701917 )
      Indirectly, via a GPS refclock.

    • Re: (Score:2)

      by devman ( 1163205 )
      List of NIST time servers here: http://tf.nist.gov/tf-cgi/serv... [nist.gov] If you want to be a good NTP citizen you probably shouldn't use these servers directly though, unless your running a very large network and syncing your own ntp servers. Some ISPs run time servers on their gateways or DNS servers, it is a decent way to get an NTP sync that is "network close" to you.

    • Re: (Score:1)

      by aliquis ( 678370 )

      It's dark outside.

      It's night.

      This wouldn't help me get to bed earlier anyway so why bother. (~04:42 local time as if it matters.)

    • ntpdate wwv.nist.gov
    • That is all.

    • In Windows 7, go to 'Change Date & Time settings', click on the 'Internet Time' tab, then 'Change settings', and in the text box, where you normally see 'time.windows.com', you can change it to 'time.nist.gov'.

      For any of the unixes, I'm guessing you'd have to edit some file in /etc to get that going.

  • so the new clock is 3x as accurate as the old one? (Score:5, Funny)

    by CrimsonAvenger ( 580665 ) on Thursday April 03, 2014 @07:01PM (#46655445)

    Well, it's important to me to be accurate within one second every three hundred million years!

    Not sure how I'd manage if my time was only accurate to one second in ONE hundred million years....

    • Re:so the new clock is 3x as accurate as the old o (Score:4, Informative)

      by mythosaz ( 572040 ) on Thursday April 03, 2014 @07:05PM (#46655505)

      NIST has vastly more accurate clocks - so I don't see what the big deal is.

      http://www.nist.gov/pml/div688... [nist.gov]

      • Re: (Score:3, Informative)

        by Anonymous Coward

        The higher-accuracy clocks are not based on Cesium, which is a necessary basis for Standards Compliance. As I understand it, the F3 clock (from the article) is a "Cesium-fountain" atomic clock and is therefore suitable for use in standards-based calculations. The clock(s) referenced in that article, on the other hand, are Mercury and Aluminum based and therefore cannot be referenced according to SI standards.. The SI governing body would have to change their standard for the other clocks to be considered,

    • Several of the sciences depend on extremely accurate timing. It's not a question of seconds lost over millions of years, but rather "how accurately can I time an event that is only a few nanoseconds long", or even better, "Exactly how far apart were these two events, even if the events are separated by hours, or days". It's misleading for the media to talk about timing in the way that they do, but apparently normal people's brains explode when someone says "nanosecond" or "parts per billion".

    • Re: (Score:2)

      by PRMan ( 959735 )
      I thought you were being funny, but it turns out you're totally serious. I didn't know the current clock was that accurate.

    • Re: (Score:2, Funny)

      by Anonymous Coward

      Would someone tell me how this happened? We were the fucking vanguard of timekeeping industry in this country. The Naval Institute was the time to keep. Then the other guy came out with accuracy of 1 part per few billion. Were we scared? Hell, no. Because we hit back with a little thing called the Atomic fucking clock. That's A for both atomic and an aloe strip. For moisture. But you know what happened next? Shut up, I'm telling you what happened—the bastards went to went all nuclear on us. They've in

    • You wouldn't want your clock to be inaccurate. I mean what if you went into stasis for 18 months and came out 300 million years later?
  • You know, the ones that will enable gps devices to be accurate to a few centimeters. That will allow robotic lawnmowers without wiring up the borders on the property, drones to airdrop missiles or fast food on my front door. Stuff like that. So what will this be good for?

  • " it will lose or gain only one second every 300 million years"

    Will it keep going for that long?

    Whats the point of time that accurate, when its going to be + or - an hoir every six months

  • ... but they will still have to manually adjust for DST twice a year.

  • gravitational time dialation (Score:5, Informative)

    by volvox_voxel ( 2752469 ) on Thursday April 03, 2014 @07:16PM (#46655695)

    I met a guy that used to work at NIST that mentioned that their clocks are so sensitive, they can tell what floor the atomic clocks are on because of of the slightly different gravitational potential each clock experiences. I wonder what kind of resolution the can resolve. Can a very massive bolder throw off the clock a little? ..perhaps one day we will have to keep better track of the local gravitational potential well. It's possible to measure the gravitational constant with simple apparatus at home. Using two massive bodies in a torsion pendulum arrangement, you can estimate "big G" -- http://www.owlnet.rice.edu/~do... [rice.edu]

    Here is an wikipedia article that mentions the phenomena with atomic clocks: http://en.wikipedia.org/wiki/G... [wikipedia.org]

  • A man with one atomic clock knows what time it is. (Score:5, Funny)

    by EmagGeek ( 574360 ) on Thursday April 03, 2014 @07:19PM (#46655727) Journal

    A man with two atomic clocks is never sure.

  • please make XP work. please.
  • Man with one atomic clock knows what time it is, man with two isn't sure.

    • man with 2 atomic clocks is a foolish man; the same money could be spent on a gps receiver that disciplines the atomic clock.

      (yes, I'm actually serious)

  • It's accurate to 1 second in 300 million years, and the development time is "about a decade"?
    I feel like my brain has whiplash reading about these differences in time precision.
  • ...to adjust the clock on 300002014/04/03 17:36:54
  • Probably compromised by the NSA.

  • posterity (Score:3)

    by loshwomp ( 468955 ) on Thursday April 03, 2014 @11:43PM (#46657795)

    it will lose or gain only one second every 300 million years

    Can't they just leave a note to the future people to click it forward/back at the right time?

    If the clock in question supports 9-digit years, they could even set an alarm...

    • Well, the 300 million years is just an estimate and it could go either forward or backward. I guess they could build a yet more accurate clock to use as a reference... :P

  • ...it's about time.

  • This may seem redundant to you. But you'll change your tune in 100 million years when the old clock is already a second out of sync while the new one is still within 0.33s.

  • ...I won't be late for meetings anymore.

  • The institute will continue operating both clocks for now at its campus in Boulder, Colorado.

    A man with one atomic clock knows the time, a man with two is never sure - every 300 million years or so, sigh.

  • I guess its not easy to sync it with the existing ones. NTP will not do the job ;).

    • You can sync it with existing clocks to an accuracy of perhaps 500 picoseconds using well-established techniques like GPS-carrier phase and Two-way Satellite Time-Transfer.

      • Re: (Score:2)

        by allo ( 1728082 )

        hmm, and the new one with the new error is then the new reference? Not that it really matters ...

        • Typically, there is no single clock that is "the reference". The international time standard, UTC, is an average of about 400 or so atomic clocks from all around the world. There are a number of caesium fountains currently contributing to UTC. Even in a single laboratory, where there a number of clocks, these clocks will usually be averaged and one clock then adjusted to keep to this average. There are various practical reasons for this. If you have a number of similar clocks, the average will have a more s

          • Re: (Score:2)

            by allo ( 1728082 )

            But isn't averaging even more unstable than syncing with one clock? And in any case, this one will be more precise than the average and every single other one.

  • Lunchtime doubly so.
  • Just wondering how many people realize that the 60HZ line frequency is eventually tied to this standard ?

  • Will they be bringing Johnny Marr in to calibrate it?

  • The NIST lab is just south of the UC Bouder campus. People in Boulder get worked up about progressive causes sometimes.

  • So... is there a technical explanation with diagrams that shows how this new clock works?

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