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

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  '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 "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-12-22 14:38 -0800
      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 "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2016-12-31 17:15 -0800
                      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 Real Troll <real.troll@trolls.com> - 2017-01-04 19:02 -0400
                              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 "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-01-04 16:35 -0800
                                Re: 'Leap Second' to Be Added on New Year's Eve This Year asetofsymbols@gmail.com - 2017-01-06 01:53 -0800
                                  Re: 'Leap Second' to Be Added on New Year's Eve This Year asetofsymbols@gmail.com - 2017-01-06 01:58 -0800
                            Re: 'Leap Second' to Be Added on New Year's Eve This Year Gene Wirchenko <genew@telus.net> - 2017-01-05 09:20 -0800
                              Re: 'Leap Second' to Be Added on New Year's Eve This Year "Rick C. Hodgin" <rick.c.hodgin@gmail.com> - 2017-01-05 10:23 -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 11:19 -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 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

Page 5 of 5 — ← Prev page 1 2 3 4 [5]

#101069

On 12/31/2016 04:57 PM, James Wilkinson Sword wrote:
> On Thu, 22 Dec 2016 13:43:58 -0000, Mr. Man-wai Chang <toylet.toylet@gmail.com> wrote:
...
>> 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

That name always struck me as rather funny - it seems to imply that 
they're responsible for making the Earth rotate. What they're actually 
responsible for is keeping track of the Earth's rotation.

>> 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.
...
> I wish they'd turn their attentions to not turning the clocks back and forth all the fucking time!

If you could make the Earth rotate at a fixed rate, there would be no 
need for leap seconds. It's perfect feasible, though the costs would be 
astronomical. Would you care to pay enough in taxes to make that happen?

[toc] | [prev] | [next] | [standalone]

#101100

On Wed, 04 Jan 2017 01:06:06 -0000, James R. Kuyper <jameskuyper@verizon.net> wrote:

> On 12/31/2016 04:57 PM, James Wilkinson Sword wrote:
>> On Thu, 22 Dec 2016 13:43:58 -0000, Mr. Man-wai Chang <toylet.toylet@gmail.com> wrote:
> ...
>>> 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
>
> That name always struck me as rather funny - it seems to imply that
> they're responsible for making the Earth rotate. What they're actually
> responsible for is keeping track of the Earth's rotation.

I am now imagining someone turning an ignition key and cursing.

>>> 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.
> ...
>> I wish they'd turn their attentions to not turning the clocks back and forth all the fucking time!
>
> If you could make the Earth rotate at a fixed rate, there would be no
> need for leap seconds. It's perfect feasible, though the costs would be
> astronomical. Would you care to pay enough in taxes to make that happen?

Rotation rate is nothing to do with DST.

-- 
Hard work pays off in the future. Laziness pays off now.

[toc] | [prev] | [next] | [standalone]

#101122

On 01/04/2017 10:44 AM, James Wilkinson Sword wrote:
> On Wed, 04 Jan 2017 01:06:06 -0000, James R. Kuyper <jameskuyper@verizon.net> wrote:
>
>> On 12/31/2016 04:57 PM, James Wilkinson Sword wrote:
>>> On Thu, 22 Dec 2016 13:43:58 -0000, Mr. Man-wai Chang <toylet.toylet@gmail.com> wrote:
>> ...
...
>>>> Leap seconds are a way to make up for this difference. Since 1972, the
>>>> International Earth Rotation and Reference Systems Service (IERS) — the
>>
>> That name always struck me as rather funny - it seems to imply that
>> they're responsible for making the Earth rotate. What they're actually
>> responsible for is keeping track of the Earth's rotation.
>
> I am now imagining someone turning an ignition key and cursing.

I was imagining a giant hand crank. :-)

>>>> 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.
>> ...
>>> I wish they'd turn their attentions to not turning the clocks back and forth all the fucking time!
>>
>> If you could make the Earth rotate at a fixed rate, there would be no
>> need for leap seconds. It's perfect feasible, though the costs would be
>> astronomical. Would you care to pay enough in taxes to make that happen?
>
> Rotation rate is nothing to do with DST.

And neither does IERS. I assumed that he was talking about leap seconds, 
thought DST also fits his complaint.

[toc] | [prev] | [next] | [standalone]

#101125

On Wed, 04 Jan 2017 19:11:30 -0000, James R. Kuyper <jameskuyper@verizon.net> wrote:

> On 01/04/2017 10:44 AM, James Wilkinson Sword wrote:
>> On Wed, 04 Jan 2017 01:06:06 -0000, James R. Kuyper <jameskuyper@verizon.net> wrote:
>>
>>> On 12/31/2016 04:57 PM, James Wilkinson Sword wrote:
>>>> On Thu, 22 Dec 2016 13:43:58 -0000, Mr. Man-wai Chang <toylet.toylet@gmail.com> wrote:
>>> ...
> ...
>>>>> Leap seconds are a way to make up for this difference. Since 1972, the
>>>>> International Earth Rotation and Reference Systems Service (IERS) — the
>>>
>>> That name always struck me as rather funny - it seems to imply that
>>> they're responsible for making the Earth rotate. What they're actually
>>> responsible for is keeping track of the Earth's rotation.
>>
>> I am now imagining someone turning an ignition key and cursing.
>
> I was imagining a giant hand crank. :-)

You must be older than me.

>>>>> 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.
>>> ...
>>>> I wish they'd turn their attentions to not turning the clocks back and forth all the fucking time!
>>>
>>> If you could make the Earth rotate at a fixed rate, there would be no
>>> need for leap seconds. It's perfect feasible, though the costs would be
>>> astronomical. Would you care to pay enough in taxes to make that happen?
>>
>> Rotation rate is nothing to do with DST.
>
> And neither does IERS. I assumed that he was talking about leap seconds,
> thought DST also fits his complaint.

-- 
Men are from Mars, Women are from Venus, Managers are from Uranus.

[toc] | [prev] | [next] | [standalone]

#101104

On 04/01/17 01:06, James R. Kuyper wrote:
> On 12/31/2016 04:57 PM, James Wilkinson Sword wrote:
>> On Thu, 22 Dec 2016 13:43:58 -0000, Mr. Man-wai Chang
>> <toylet.toylet@gmail.com> wrote:
> ...
>>> 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
>
> That name always struck me as rather funny - it seems to imply that
> they're responsible for making the Earth rotate. What they're actually
> responsible for is keeping track of the Earth's rotation.
>
>>> 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.
> ...
>> I wish they'd turn their attentions to not turning the clocks back and
>> forth all the fucking time!
>
> If you could make the Earth rotate at a fixed rate, there would be no
> need for leap seconds. It's perfect feasible, though the costs would be
> astronomical. Would you care to pay enough in taxes to make that happen?


You missed his point. He's not talking about leap seconds now, but about 
Daylight Saving Time. He thinks it's stupid that we keep putting our 
clocks forward an hour in the spring and an hour back in the evening --- 
and he's right. Those who are familiar with his output should not be 
/too/ surprised that he's right --- even a stopped clock can be right 
twice a day.


-- 
Richard Heathfield
Email: rjh at cpax dot org dot uk
"Usenet is a strange place" - dmr 29 July 1999
Sig line 4 vacant - apply within

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#101131

On Wed, 04 Jan 2017 16:17:12 -0000, Richard Heathfield <rjh@cpax.org.uk> wrote:

> On 04/01/17 01:06, James R. Kuyper wrote:
>> On 12/31/2016 04:57 PM, James Wilkinson Sword wrote:
>>> On Thu, 22 Dec 2016 13:43:58 -0000, Mr. Man-wai Chang
>>> <toylet.toylet@gmail.com> wrote:
>> ...
>>>> 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
>>
>> That name always struck me as rather funny - it seems to imply that
>> they're responsible for making the Earth rotate. What they're actually
>> responsible for is keeping track of the Earth's rotation.
>>
>>>> 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.
>> ...
>>> I wish they'd turn their attentions to not turning the clocks back and
>>> forth all the fucking time!
>>
>> If you could make the Earth rotate at a fixed rate, there would be no
>> need for leap seconds. It's perfect feasible, though the costs would be
>> astronomical. Would you care to pay enough in taxes to make that happen?
>
>
> You missed his point. He's not talking about leap seconds now, but about
> Daylight Saving Time. He thinks it's stupid that we keep putting our
> clocks forward an hour in the spring and an hour back in the evening ---
> and he's right. Those who are familiar with his output should not be
> /too/ surprised that he's right --- even a stopped clock can be right
> twice a day.

Also, I've yet to see a reason why we can't just live with being 1 second different to sunrise....

-- 
Do infants have as much fun in their infancy as adults do in adultery?

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#101201

"James Wilkinson Sword" wrote:

>Also, I've yet to see a reason why we can't just live with being 1 second 
>different to sunrise....

I think we can.  But since there is more than a minutes error accumulated 
during a person's lifetime, I am glad someone is doing this.

I am fascinated by the fact that they *can* do this. I would assume that 
this requires rough agreement (a few milliseconds difference) between 
measurements made at  different observatories.  These are on different 
plates of this earth, and these plates are drifting, earthquakes are moving 
the observatories, and so on. .

GPS is not an answer, it intrinsically has the same problems. 

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#101211

On Thu, 05 Jan 2017 20:15:14 -0000, Osmium <r124c4u102@comcast.net> wrote:

> "James Wilkinson Sword" wrote:
>
>> Also, I've yet to see a reason why we can't just live with being 1 second
>> different to sunrise....
>
> I think we can.  But since there is more than a minutes error accumulated
> during a person's lifetime, I am glad someone is doing this.
>
> I am fascinated by the fact that they *can* do this. I would assume that
> this requires rough agreement (a few milliseconds difference) between
> measurements made at  different observatories.  These are on different
> plates of this earth, and these plates are drifting, earthquakes are moving
> the observatories, and so on. .
>
> GPS is not an answer, it intrinsically has the same problems.

My god if you got up and had to wait a whole minute extra for the sun to rise, it would sure screw your head up wouldn't it?

-- 
Warning: Do not attempt to stop chainsaw with testicles.

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#101194

In comp.lang.ada James R. Kuyper <jameskuyper@verizon.net> wrote:
> On 12/31/2016 04:57 PM, James Wilkinson Sword wrote:
> > On Thu, 22 Dec 2016 13:43:58 -0000, Mr. Man-wai Chang <toylet.toylet@gmail.com> wrote:
> ...
> >> 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
> 
> That name always struck me as rather funny - it seems to imply that 
> they're responsible for making the Earth rotate. What they're actually 
> responsible for is keeping track of the Earth's rotation.
> 
> >> 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.
> ...
> > I wish they'd turn their attentions to not turning the clocks back and forth all the fucking time!
> 
> If you could make the Earth rotate at a fixed rate, there would be no 
> need for leap seconds. It's perfect feasible, though the costs would be 
> astronomical. Would you care to pay enough in taxes to make that happen?

Changing _time_ is a nonsense and Earth rotation has little to
do with this:

- most of ordinary time use is conventional and shift of few minutes
  will not chage much.  AFAICS to accumulate 5 minutes difference
  we need hundreds of years, plenty of time to update conventions
  if needed.  In precision use jumping time is bigger hurdle than
  help: astonomers care about differences much smaller than a
  second.
- if one really wants to follow Earth rotation time base still
  should be continous and at most mapping from "universal" to
  "local" time should change.  Given that basic time unit is
  second we probably should designate one specific moment as
  start of rational era and simply measure time in second
  relative to this moment.  UTC could be reasonable approximation
  to rational time, but leap seconds spoil its properties.

-- 
                              Waldek Hebisch

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#101205

On Thu, 05 Jan 2017 19:28:59 -0000, <antispam@math.uni.wroc.pl> wrote:

> In comp.lang.ada James R. Kuyper <jameskuyper@verizon.net> wrote:
>> On 12/31/2016 04:57 PM, James Wilkinson Sword wrote:
>> > On Thu, 22 Dec 2016 13:43:58 -0000, Mr. Man-wai Chang <toylet.toylet@gmail.com> wrote:
>> ...
>> >> 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
>>
>> That name always struck me as rather funny - it seems to imply that
>> they're responsible for making the Earth rotate. What they're actually
>> responsible for is keeping track of the Earth's rotation.
>>
>> >> 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.
>> ...
>> > I wish they'd turn their attentions to not turning the clocks back and forth all the fucking time!
>>
>> If you could make the Earth rotate at a fixed rate, there would be no
>> need for leap seconds. It's perfect feasible, though the costs would be
>> astronomical. Would you care to pay enough in taxes to make that happen?
>
> Changing _time_ is a nonsense and Earth rotation has little to
> do with this:
>
> - most of ordinary time use is conventional and shift of few minutes
>   will not chage much.  AFAICS to accumulate 5 minutes difference
>   we need hundreds of years, plenty of time to update conventions
>   if needed.  In precision use jumping time is bigger hurdle than
>   help: astonomers care about differences much smaller than a
>   second.
> - if one really wants to follow Earth rotation time base still
>   should be continous and at most mapping from "universal" to
>   "local" time should change.  Given that basic time unit is
>   second we probably should designate one specific moment as
>   start of rational era and simply measure time in second
>   relative to this moment.  UTC could be reasonable approximation
>   to rational time, but leap seconds spoil its properties.

+1

-- 
Money can't buy you true love.
It does however put you in a good bargaining position.

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#100850

On 12/22/2016 01:43 PM, Mr. Man-wai Chang wrote:
> '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.

My question is how this will affect computer programs that convert Unix
Julian time (which keeps time in seconds since 00:00:00 UTC 01 Jan
1970).

For example, I have various Perl modules that convert Unix time to
readable timestamps.  If my module doesn't include for the leap second,
will my timestamps be one second off?  I assume they'll update the
myriad of programming language modules, but how long will this take?
For now, I'll assume the current Perl module has been updated.

(BTW, I was watching the Berlin clock on timeanddate.com, and their
clock went from 23:59:59 to 00:00:00 -- there was no "23:59:60").

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#100851

Dänk 42Ø <dank@nugget.org> writes:
[...]
> My question is how this will affect computer programs that convert Unix
> Julian time (which keeps time in seconds since 00:00:00 UTC 01 Jan
> 1970).

That's just Unix time; it's not "Julian".

> For example, I have various Perl modules that convert Unix time to
> readable timestamps.  If my module doesn't include for the leap second,
> will my timestamps be one second off?  I assume they'll update the
> myriad of programming language modules, but how long will this take?
> For now, I'll assume the current Perl module has been updated.

Typically Unix systems ignore leap seconds.  For example, on my system's
timestamp as I write this is 1483342650, though allowing for the 37
intervening leap seconds, 1970-01-01 00:00:00 UTC was actually
1483342687 seconds ago.  The slightly incorrect representation of old
date isn't much of a problem in practice.

The system clock was probably adjusted gradually during the period
before and after the leap second.

> (BTW, I was watching the Berlin clock on timeanddate.com, and their
> clock went from 23:59:59 to 00:00:00 -- there was no "23:59:60").

time.gov showed 23:59:60.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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#100913

On 01/02/2017 07:46 AM, Keith Thompson wrote:
> Dänk 42Ø <dank@nugget.org> writes:
> [...]
>> My question is how this will affect computer programs that convert Unix
>> Julian time (which keeps time in seconds since 00:00:00 UTC 01 Jan
>> 1970).
>
> That's just Unix time; it's not "Julian".
>
>> For example, I have various Perl modules that convert Unix time to
>> readable timestamps.  If my module doesn't include for the leap second,
>> will my timestamps be one second off?  I assume they'll update the
>> myriad of programming language modules, but how long will this take?
>> For now, I'll assume the current Perl module has been updated.
>
> Typically Unix systems ignore leap seconds.  For example, on my system's
> timestamp as I write this is 1483342650, though allowing for the 37
> intervening leap seconds, 1970-01-01 00:00:00 UTC was actually
> 1483342687 seconds ago.  The slightly incorrect representation of old
> date isn't much of a problem in practice.
>
> The system clock was probably adjusted gradually during the period
> before and after the leap second.

But since computers store files with Unix time strings, how is is that
a recently saved file shows the correct current time and is not 37
seconds off?  Obviously, the software is accounting for those leap
seconds?  Or maybe you're referring to the SYSTEM time, which is
adjusted, but makes dating really old files difficult since I don't
what system they came from or whether they adjusted for leap seconds.
A very trivial matter, especially with old files, but a very
important one today, where files are timestamped down to the milli-
second.


>> (BTW, I was watching the Berlin clock on timeanddate.com, and their
>> clock went from 23:59:59 to 00:00:00 -- there was no "23:59:60").
>
> time.gov showed 23:59:60.

Shoulda gone there.  I was especially interested in Berlin's New Year,
as I was following the German news to see whether a terrorist attack
occurred at that moment.

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#100925

Dänk 42Ø <dank@nugget.org> writes:
> On 01/02/2017 07:46 AM, Keith Thompson wrote:
[...]
>> The system clock was probably adjusted gradually during the period
>> before and after the leap second.
>
> But since computers store files with Unix time strings, how is is that
> a recently saved file shows the correct current time and is not 37
> seconds off?

In fact the timestamp of a file created in 1970 *is* 37 seconds off.
I don't have any files that old, but the timestamp of a file created
in 2016 is now 1 second off, and will be 2 seconds off after the
next leap second.

I'll bet you didn't notice.  As long as timestamps are monotonically
increasing, it doesn't significantly matter.

If you need to record timestamps from several years ago with higher
precision, and allowing for leap seconds, there are other time
representations you can use.  It just happens that Unix filesystems
don't typically use them (though it's entirely possible that there
are some I don't know about that do).

Relevance to C: The C standard says only that time_t, the type
returned by the time() function, is a real time (integer or
floating-point) capable of representing times.  POSIX specifically
says that leap seconds are ignored.  This implies, for example,
that time(NULL) % 3600 is the number of seconds since the top of
the hour, and that system software doesn't have to allow for past
leap seconds (which would be inconvenient) or future leap seconds
(which would be impossible).

[...]

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
Working, but not speaking, for JetHead Development, Inc.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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#101070

On 01/02/2017 02:08 AM, Dänk 42Ø wrote:
...
> (BTW, I was watching the Berlin clock on timeanddate.com, and their
> clock went from 23:59:59 to 00:00:00 -- there was no "23:59:60").

The leap second occurred at the same time all around the world, not at 
the same local time (that would have been a nightmare for anybody who 
needs to keep track of local time in multiple time zones with sub-second 
precision!). The Berlin clock should therefore have gone from 00:59:59 
to 00:59:60 (if it correctly reflected leap seconds), since it's in the 
CET time zone.

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