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Leap Second At The End of 2005

Posted by CmdrTaco on from the correct-your-watches-immediately dept.

Ruff_ilb writes "Because of the discrepency between an ephemeris second (the fraction 1/31,556,925.9747 of the tropical year for 1900 January 0 at 12 hours ephemeris time) and the second of atomic time (the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom), we're left with more than leap years. In order to ensure that the the atomic time and civil stay coordinated, "Civil time is occasionally adjusted by one second increments to ensure that the difference between a uniform time scale defined by atomic clocks does not differ from the Earth's rotational time by more than 0.9 seconds."" And Happy New Years everyone ;)

2 of 269 comments (clear)

  1. Re:How did you use yours? by Extrudedaluminiu · · Score: 5, Interesting

    Do any NTP servers keep track of these seconds?

    --
    -vs, me@acm.jhu.edu
  2. Log of Atomic GPS Clock adjustment by BiggRanger · · Score: 5, Interesting

    I did up a project on sourceforge.net a few years back to sync my computers with a GPS http://atomicgpsclock.sourceforge.net/. Below is a log of the activity, normally there is a +/- 0.016 or so second instability, but 18:59:59 EST (or 23:59:59 UTC) the Navy made a 1 second adjustment to the GPS system, and it's vibible in the log at the next scheduled sync (in bold)

    2005.12.31 18:33:49 00032 GPS Status - Tracking: 3D
    2005.12.31 18:43:27 00020 Offset: 000.016 Buffer: 13
    2005.12.31 18:43:27 00032 GPS Status - Tracking: 3D
    2005.12.31 18:43:49 00020 Offset: -000.031 Buffer: 13
    2005.12.31 18:43:49 00032 GPS Status - Tracking: 3D
    2005.12.31 18:45:15 00033 GPS Status - Tracking: No
    2005.12.31 18:45:34 00032 GPS Status - Tracking: 1D
    2005.12.31 18:46:48 00033 GPS Status - Tracking: No
    2005.12.31 18:46:52 00032 GPS Status - Tracking: 3D
    2005.12.31 19:01:43 00033 GPS Status - Tracking: No
    2005.12.31 19:01:55 00032 GPS Status - Tracking: 1D
    2005.12.31 19:03:45 00020 Offset: 001.016 Buffer: 13
    2005.12.31 19:03:45 00032 GPS Status - Tracking: 2D
    2005.12.31 19:13:45 00020 Offset: -000.016 Buffer: 13
    2005.12.31 19:13:45 00032 GPS Status - Tracking: 3D
    2005.12.31 19:23:43 00020 Offset: 000.000 Buffer: 13
    2005.12.31 19:23:43 00032 GPS Status - Tracking: 3D
    2005.12.31 19:33:43 00020 Offset: 000.000 Buffer: 13
    2005.12.31 19:33:43 00032 GPS Status - Tracking: 3D
    2005.12.31 19:43:30 00033 GPS Status - Tracking: No
    2005.12.31 19:43:40 00032 GPS Status - Tracking: 1D
    2005.12.31 19:53:41 00020 Offset: -000.031 Buffer: 13
    2005.12.31 19:53:41 00032 GPS Status - Tracking: 3D
    2005.12.31 20:03:39 00020 Offset: 000.000 Buffer: 13
    2005.12.31 20:03:39 00032 GPS Status - Tracking: 3D