[LEAPSECS] WP7A status and Re: clinical evidence about time and sun

[Rob Seaman]

On Dec 18, 2008, at 3:13 PM, Poul-Henning Kamp wrote:


> Before the first timezone ever shifts to compensate for the abandoned

> leapseconds, that number is almost certain to have increased to at

> least two and likely more irregular rocks.


Scroll back the the very beginning of the archives.  I had some sort  
of response to a similar assertion from Demetrios Matsakis's original  
survey.  I might even still agree with it, if I read it again :-)


> Which reminds me: you have never answered my question:

>

> Why should mumans on Mars or the Moon, care about the rotation of

> a rock they are not on when they want to time events ?


Well, because they likely want to communicate with their families back  
on Earth, I suppose, but again you are making my point.  What are you  
asserting here?  That people living on Mars will clearly want to keep  
Martian time?  I believe that completely.  Martian civil time will  
clearly be mean solar time on Mars.

I don't intrinsically care about leap seconds, other than as a means  
to an end.  I care about maintaining the obvious connection between  
civil timekeeping and some functional flavor of mean solar time.


> Isn't it bad enough that relativity messes them up ?


This sounds like an interesting question, but you are discussing facts  
(or not facts) that haven't been entered into evidence.


> And I still find it utterly ironic, that people like you attempt

> to lock the timescale which has "Universal" in its name to a

> particular piece of rock with known bad timekeeping properties.


People like me don't particularly care about the "fossil poetry" (as  
Emerson calls it) of the origin of word phrases - at least not as far  
as usage is concerned.  UTC has been defined as a flavor of UT.  The  
original wording of the UTC standard (if I can call it that) included  
the clear statement:

	"GMT may be regarded as the general equivalent of UT."

Ignore everything else we've ever discussed.  The central issue with  
several of us is that the meaning of the UTC standard should not be  
changed.  If a decision (ideally a calm, reasoned and publicly  
transparent decision) is made to relayer civil timekeeping on a clock  
without leap seconds, then don't call that clock "UTC".

How about calling it - say - GPS?  The public already knows GPS,  
already owns devices that speak it, and already regards it as a brand  
name denoting high precision/accuracy timekeeping.


> A timescale which takes earth rotation into account should be

> called "Terrestial Time Coordinated" (TTC ?) and the timescale

> that takes into account the rotation of Mars should be MTC.


Go for it!  I have no particular opinion on this subject (well - yet -  
depending on how bizarre the political machinations become :-)  The  
difference between this suggestion and the ongoing discussion of UTC  
is that UTC has a long tangled history.  If you want to cut that  
tangle, do what Alexander did with the Gordian Knot - cleave it in  
half entirely by referencing a completely new timescale lacking in  
prior complications.


> But the universal timescale should depend on nothing that is not

> uniform throughout the Universe.


This is a misuse of the multiple meanings of the word "universal".  My  
TV receives a cable channel called "Universal HD".  Should I take them  
to court for misrepresentation?  What about Universal Studios or a  
universal remote control?

Rob