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NIST Unveils Chip-scale Atomic Clock

Posted by CmdrTaco on from the and-it-fits-in-the-oh-never-mind dept.

grumling writes "The heart of a minuscule atomic clock, believed to be 100 times smaller than any other atomic clock has been demonstrated by scientists at the Commerce Department's National Institute of Standards and Technology (NIST), opening the door to atomically precise timekeeping in portable, battery-powered devices for secure wireless communications, more precise navigation and other applications. "

7 of 172 comments (clear)

  1. At last... by Aardpig · · Score: 3, Informative

    ...Netgear can start manufacturing routers that don't totally fuck the NTP server at University of Wisconsin, Madison.

    --
    Tubal-Cain smokes the white owl.
  2. BAD advice. Do NOT do this. by vadim_t · · Score: 3, Informative

    That's a very good way of getting blocked at firewall level. It's rather stupid too, since if you need so much precision just use NTP instead.

    It is a wrong use of ntpdate as well. Its point is to set the time to the correct one at startup, since ntpd only makes gradual corrections and won't make time go backwards for example to avoid breaking things.

    So, configure ntpdate to run once at boot, then start ntpd to keep it in sync.

  3. Re:Atomic clock? by UnknowingFool · · Score: 4, Informative
    Actually, by definition, something atomic is very small.

    Most of the time that is true but in this case, an atomic clock has a very precise meaning in scientific instruments. It is a clock that counts the vibrations of atoms to determine time intervals. Accoring to SI units a second is

    a fundamental unit of time in all measuring systems and the SI base unit of time. The name simply means that this unit is the second division of the hour, the minute being the first. The second was defined as 1/86 400 mean solar day until astronomers discovered that the mean solar day is actually not constant (see day). The definition was then changed to 1/86 400 of the mean solar day 1900 January 1. Since we can't go back and measure that day any more, this wasn't a real solution to the problem. In 1967, scientists agreed to define the second as that period of time which makes the frequency of a certain radiation emitted by atoms of cesium-133 equal to 9 192 631 770 hertz (cycles per second). In other words, if we really want to measure a second, we count 9 192 631 770 cycles of this radiation. This definition allows scientists to reconstruct the second anywhere in the world with equal precision.

    Up until now atomic clocks like the ones used by NIST were large pieces of equipment. They were highly accurate but not very portable. Before, merchanical watches would lose seconds a day. With the use of quartz in electronic watches that dropped to about a second every 2 months. This lowers that bar even further. I'm not sure for what that level of precision could be used.

    --
    Well, there's spam egg sausage and spam, that's not got much spam in it.
  4. Re:OK, so when do I get one in my PC... by Gerald · · Score: 3, Informative

    So why don't you just use NTPd or OpenNTPd? And why aren't you using pool.ntp.org instead of picking on the poor, overloaded NIST servers?

  5. Re:OK, so when do I get one in my PC... by Artifakt · · Score: 3, Informative

    There are about a jillion clock programs for windows that call the NIST clocks on a regular schedule of your choice and adjust the PC. Most of them are freeware. Some of them work with a clock display on desktop, some with the existing clock in the systray. I recomend Beatnik, at http://www.somedec.com/ free, skinnable, and stable, and no I don't have any connection to the author except using it and some of his other freeware. However, the OP apparently doesn't want to do something like that. I confess, I'm not sure why. If he has a box whose clock drifts by 5 min a day and that once daily ping is eating up substantial time on his connection, the answer is to get a new box or a faster connection. If my clock naturally drifted by 5 minutes a day, I'd want to correct about every 4 hours or so, or maybe I'd just immediatly try replacing the Mobo battery in case that was a sign it was going stale. Maybe I'm missing something there, and he just doesn't want to go through the process manually, but it sounds like he's more wanting to not do it at all.

    --
    Who is John Cabal?
  6. Re:Not everybody has permanent connection! by vadim_t · · Score: 4, Informative

    You still can do it.

    Just run ntpdate when you connect instead of on boot. And kill ntpd before disconnecting. You can do this easily on Linux. On Windows I heard some programs exist to do this as well.

    This is not about broadband arrogance anyway. ntpd uses much fewer server resources than ntpdate every second. In fact, many public ntp server administrators often complain about that every hour at :00 minutes they get a ntp version of a slashdotting because people stick ntpdate in crontab.

    There are many NTP servers that are free to access out there. Please keep them that way by observing a simple netiquette.

  7. Re:Great for GPS by Anonymous Coward · · Score: 4, Informative
    The Navy has been using atomic clocks for decades. Much of the technology in GPS can be traced back to early Navy programs for satellite assisted navigation. When you launch an ICBM from a submarine, you need a very accurate fix on the position of the submarine. Atomic clocks are also as timing references for secure communications links.

    In fact, the entire history of accurate time can be attributed to naval navigation.