Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > comp.programming > #7182

'Leap Second' to Be Added on New Year's Eve This Year

From "Mr. Man-wai Chang" <toylet.toylet@gmail.com>
Newsgroups alt.comp.hardware.pc-homebuilt, comp.lang.c, comp.lang.ada, comp.programming, alt.comp.os.windows-10, alt.os.linux.ubuntu
Subject 'Leap Second' to Be Added on New Year's Eve This Year
Date 2016-12-22 21:43 +0800
Organization Hung Hom, Kowloon, Hong Kong
Message-ID <o3gl85$j26$1@dont-email.me> (permalink)

Cross-posted to 6 groups.

Show all headers | View raw


'Leap Second' to Be Added on New Year's Eve This Year

Full story: <http://www.space.com/33361-leap-second-2016-atomic-clocks.html>

  Revelers will get to celebrate New Year's Eve for a tiny bit longer 
than usual this year.

A "leap second" will be added to the world's official clocks on Dec. 31 
at 23 hours, 59 minutes and 59 seconds Coordinated Universal Time (UTC), 
which corresponds to 6:59:59 p.m. EST; the clocks will read 23:59:60 
before ticking over to midnight. The goal is to keep two different 
timescales in sync with each other.

The units of time had long been defined based on Earth's rotation 
relative to distant celestial bodies. But that changed with the 
invention of atomic clocks in the mid-20th century; scientists then 
decided to base the second on the natural vibrations of the cesium atom. 
[How to Build the Most Accurate Atomic Clocks (Video)]

These two timescales don't match up exactly, however. Measurements show 
that, because the moon's gravitational pull and other factors are 
gradually slowing Earth's spin, the rotation-based scale loses between 
1.5 and 2 milliseconds per day compared to atomic time — meaning the two 
diverge by a full second every 500 to 750 days.

Leap seconds are a way to make up for this difference. Since 1972, the 
International Earth Rotation and Reference Systems Service (IERS) — the 
organization that keeps track of time for the world — has added 26 leap 
seconds to atomic clocks, with the last such insertion coming on June 
30, 2015.

  The aim is to keep the two timescales within 0.9 seconds of each other.

"We can easily change the time of an atomic clock, but it is not 
possible to alter the Earth's rotational speed to match the atomic 
clocks," officials with the U.S. Naval Observatory (USNO), which 
maintains the Department of Defense's master clock, noted — wryly, it 
would seem — in a statement today (July 6).

While Earth's rotation rate is slowing, the effect is quite subtle.

"Confusion sometimes arises over the misconception that the occasional 
insertion of leap seconds every few years indicates that the Earth 
should stop rotating within a few millennia," USNO officials wrote. 
"This is because some [people] mistake leap seconds to be a measure of 
the rate at which the Earth is slowing. The 1-second increments are, 
however, indications of the accumulated difference in time between the 
two systems."

When leap seconds are added, they are always inserted on June 30 or Dec. 
31 of a particular year. In 1972, IERS officials called for a leap 
second to be inserted on both dates.

Back to comp.programming | Previous | Next — Next in thread | Find similar | Unroll thread


Thread

'Leap Second' to Be Added on New Year's Eve This Year "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-12-22 21:43 +0800
  Re: 'Leap Second' to Be Added on New Year's Eve This Year Siri Cruise <chine.bleu@yahoo.com> - 2016-12-22 05:48 -0800
    Re: 'Leap Second' to Be Added on New Year's Eve This Year "Mr. Man-wai Chang" <toylet.toylet@gmail.com> - 2016-12-22 22:09 +0800
    Re: 'Leap Second' to Be Added on New Year's Eve This Year Krzysztof Mitko <invalid@kmitko.at.list.dot.pl> - 2016-12-24 13:47 +0100
      Re: 'Leap Second' to Be Added on New Year's Eve This Year Siri Cruise <chine.bleu@yahoo.com> - 2016-12-24 05:39 -0800
  Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Lloyd <not@mail.invalid> - 2016-12-22 14:31 -0600
    Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Storkamp <mstorkamp@yahoo.com> - 2016-12-23 08:34 -0600
      Re: 'Leap Second' to Be Added on New Year's Eve This Year "J-P. Rosen" <rosen@adalog.fr> - 2016-12-23 16:55 +0100
      Re: 'Leap Second' to Be Added on New Year's Eve This Year Ken Brody <kenbrody@spamcop.net> - 2016-12-30 11:17 -0500
        Re: 'Leap Second' to Be Added on New Year's Eve This Year Gene Wirchenko <genew@telus.net> - 2016-12-30 09:38 -0800
          Re: 'Leap Second' to Be Added on New Year's Eve This Year hah <hah@no.email.stupid.invalid> - 2016-12-30 15:59 -0600
        Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Lloyd <not@mail.invalid> - 2016-12-30 15:47 -0600
        Re: 'Leap Second' to Be Added on New Year's Eve This Year Ken Blake <Ken@invalid.news.com> - 2016-12-30 15:14 -0700
          Re: 'Leap Second' to Be Added on New Year's Eve This Year Kaz Kylheku <221-501-9011@kylheku.com> - 2016-12-30 23:26 +0000
    Re: 'Leap Second' to Be Added on New Year's Eve This Year "James R. Kuyper" <jameskuyper@verizon.net> - 2017-01-03 20:46 -0500
  Re: 'Leap Second' to Be Added on New Year's Eve This Year Jason <jason_warren@ieee.DELETE.org> - 2016-12-22 17:14 -0500
    Re: 'Leap Second' to Be Added on New Year's Eve This Year "Jonathan N. Little" <lws4art@gmail.com> - 2016-12-22 17:40 -0500
      Re: 'Leap Second' to Be Added on New Year's Eve This Year Jason <jason_warren@ieee.org> - 2016-12-23 19:57 -0500
        Re: 'Leap Second' to Be Added on New Year's Eve This Year Char Jackson <none@none.invalid> - 2016-12-23 21:44 -0600
          Re: 'Leap Second' to Be Added on New Year's Eve This Year "James Wilkinson Sword" <imvalid@somewear.com> - 2016-12-31 23:42 +0000
    Re: 'Leap Second' to Be Added on New Year's Eve This Year Ken Brody <kenbrody@spamcop.net> - 2016-12-30 11:16 -0500
      Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Lloyd <not@mail.invalid> - 2016-12-30 15:58 -0600
        Re: 'Leap Second' to Be Added on New Year's Eve This Year Keith Thompson <kst-u@mib.org> - 2016-12-30 14:37 -0800
          Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Lloyd <not@mail.invalid> - 2016-12-30 19:16 -0600
            Re: 'Leap Second' to Be Added on New Year's Eve This Year Keith Thompson <kst-u@mib.org> - 2016-12-30 17:48 -0800
              Re: 'Leap Second' to Be Added on New Year's Eve This Year Jorgen Grahn <grahn+nntp@snipabacken.se> - 2016-12-31 10:08 +0000
              Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Lloyd <not@mail.invalid> - 2016-12-31 14:20 -0600
              Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Lloyd <not@mail.invalid> - 2016-12-31 14:34 -0600
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Wally W. <ww84wa@aim.com> - 2016-12-31 16:45 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Ken Blake <Ken@invalid.news.com> - 2016-12-31 16:34 -0700
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Wally W. <ww84wa@aim.com> - 2016-12-31 20:52 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Richard Heathfield <rjh@cpax.org.uk> - 2017-01-01 12:22 +0000
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Lloyd <not@mail.invalid> - 2017-01-01 15:47 -0600
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Keith Thompson <kst-u@mib.org> - 2016-12-31 13:59 -0800
              Re: 'Leap Second' to Be Added on New Year's Eve This Year Wally W. <ww84wa@aim.com> - 2017-01-01 13:46 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Lloyd <not@mail.invalid> - 2017-01-01 16:12 -0600
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Wally W. <ww84wa@aim.com> - 2017-01-01 19:44 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Wally W. <ww84wa@aim.com> - 2017-01-01 22:31 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Ken Blake <Ken@invalid.news.com> - 2017-01-02 11:23 -0700
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Lloyd <not@mail.invalid> - 2017-01-02 19:03 -0600
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Storkamp <mstorkamp@yahoo.com> - 2017-01-02 13:46 -0600
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Wolf K <wolfmac@sympatico.ca> - 2017-01-02 14:55 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Andy Burns <usenet@andyburns.uk> - 2017-01-02 20:00 +0000
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Sam E <why.should.this@be.email.invalid> - 2017-01-02 19:07 -0600
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Gareth Owen <gwowen@gmail.com> - 2017-01-03 06:45 +0000
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Wolf K <wolfmac@sympatico.ca> - 2017-01-03 09:42 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year "Cybe R. Wizard" <cybe_r_wizard@WizardsTower.invalid> - 2017-01-03 11:27 -0600
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Caver1 <caver1@inthemud.org> - 2017-01-03 14:25 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year "James R. Kuyper" <jameskuyper@verizon.net> - 2017-01-03 17:34 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Storkamp <mstorkamp@yahoo.com> - 2017-01-02 14:20 -0600
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Wolf K <wolfmac@sympatico.ca> - 2017-01-02 15:36 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year "James R. Kuyper" <jameskuyper@verizon.net> - 2017-01-04 12:09 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Wolf K <wolfmac@sympatico.ca> - 2017-01-04 19:12 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Wally W. <ww84wa@aim.com> - 2017-01-02 15:06 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Lloyd <not@mail.invalid> - 2017-01-02 19:10 -0600
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Wally W. <ww84wa@aim.com> - 2017-01-02 22:56 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year "James R. Kuyper" <jameskuyper@verizon.net> - 2017-01-04 12:34 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Lloyd <not@mail.invalid> - 2017-01-04 15:32 -0600
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Keith Thompson <kst-u@mib.org> - 2017-01-04 13:51 -0800
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Lloyd <not@mail.invalid> - 2017-01-04 22:37 -0600
                Re: 'Leap Second' to Be Added on New Year's Eve This Year "James R. Kuyper" <jameskuyper@verizon.net> - 2017-01-04 17:21 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Gene Wirchenko <genew@telus.net> - 2017-01-05 09:20 -0800
                [OT] Meaning and truth (Was Re: 'Leap Second' to Be Added on New Year's Eve This Year) Wolf K <wolfmac@sympatico.ca> - 2017-01-05 13:34 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Caver1 <caver1@inthemud.org> - 2017-01-07 17:20 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Kaz Kylheku <221-501-9011@kylheku.com> - 2017-01-07 22:57 +0000
                Re: 'Leap Second' to Be Added on New Year's Eve This Year "James R. Kuyper" <jameskuyper@verizon.net> - 2017-01-07 19:06 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Kaz Kylheku <221-501-9011@kylheku.com> - 2017-01-08 06:16 +0000
                Re: 'Leap Second' to Be Added on New Year's Eve This Year "James R. Kuyper" <jameskuyper@verizon.net> - 2017-01-08 10:26 -0500
                Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Lloyd <not@mail.invalid> - 2017-01-02 19:05 -0600
                Re: 'Leap Second' to Be Added on New Year's Eve This Year "James Wilkinson Sword" <imvalid@somewear.com> - 2017-01-04 00:28 +0000
            Re: 'Leap Second' to Be Added on New Year's Eve This Year raltbos@xs4all.nl (Richard Bos) - 2017-01-01 10:01 +0000
          Re: 'Leap Second' to Be Added on New Year's Eve This Year Mark Lloyd <not@mail.invalid> - 2016-12-31 14:29 -0600
  Re: 'Leap Second' to Be Added on New Year's Eve This Year "James Wilkinson Sword" <imvalid@somewear.com> - 2016-12-31 21:57 +0000
    Re: 'Leap Second' to Be Added on New Year's Eve This Year "James R. Kuyper" <jameskuyper@verizon.net> - 2017-01-03 20:06 -0500
      Re: 'Leap Second' to Be Added on New Year's Eve This Year "James Wilkinson Sword" <imvalid@somewear.com> - 2017-01-04 15:44 +0000
        Re: 'Leap Second' to Be Added on New Year's Eve This Year "James R. Kuyper" <jameskuyper@verizon.net> - 2017-01-04 14:11 -0500
          Re: 'Leap Second' to Be Added on New Year's Eve This Year "James Wilkinson Sword" <imvalid@somewear.com> - 2017-01-04 19:58 +0000
      Re: 'Leap Second' to Be Added on New Year's Eve This Year Richard Heathfield <rjh@cpax.org.uk> - 2017-01-04 16:17 +0000
        Re: 'Leap Second' to Be Added on New Year's Eve This Year "James Wilkinson Sword" <imvalid@somewear.com> - 2017-01-04 21:03 +0000
          Re: 'Leap Second' to Be Added on New Year's Eve This Year "Osmium" <r124c4u102@comcast.net> - 2017-01-05 14:15 -0600
            Re: 'Leap Second' to Be Added on New Year's Eve This Year "James Wilkinson Sword" <imvalid@somewear.com> - 2017-01-06 01:26 +0000
          Re: 'Leap Second' to Be Added on New Year's Eve This Year raltbos@xs4all.nl (Richard Bos) - 2017-01-09 17:12 +0000
            Re: 'Leap Second' to Be Added on New Year's Eve This Year Har-dee-har-har <YouMustBeKidding@This.Com> - 2017-01-09 09:53 -0800
              Re: 'Leap Second' to Be Added on New Year's Eve This Year "J-P. Rosen" <rosen@adalog.fr> - 2017-01-10 07:20 +0100
            Re: 'Leap Second' to Be Added on New Year's Eve This Year "James Wilkinson Sword" <imvalid@somewear.com> - 2017-01-12 23:17 +0000
              Re: 'Leap Second' to Be Added on New Year's Eve This Year Tim <timothybil@yahoo.com> - 2017-01-13 00:51 -0600
      Re: 'Leap Second' to Be Added on New Year's Eve This Year antispam@math.uni.wroc.pl - 2017-01-05 19:28 +0000
        Re: 'Leap Second' to Be Added on New Year's Eve This Year "James Wilkinson Sword" <imvalid@somewear.com> - 2017-01-05 21:41 +0000
  Re: 'Leap Second' to Be Added on New Year's Eve This Year Dänk 42Ø <dank@nugget.org> - 2017-01-02 07:08 +0000
    Re: 'Leap Second' to Be Added on New Year's Eve This Year Keith Thompson <kst-u@mib.org> - 2017-01-01 23:46 -0800
      Re: 'Leap Second' to Be Added on New Year's Eve This Year Dänk 42Ø <dank@nugget.org> - 2017-01-02 21:56 +0000
        Re: 'Leap Second' to Be Added on New Year's Eve This Year Keith Thompson <kst-u@mib.org> - 2017-01-02 15:38 -0800
    Re: 'Leap Second' to Be Added on New Year's Eve This Year "James R. Kuyper" <jameskuyper@verizon.net> - 2017-01-03 20:26 -0500

csiph-web