[time-nuts] Loran-C & French Clocks

Magnus Danielson magnus at rubidium.dyndns.org
Tue Mar 17 23:36:03 UTC 2009


Arnold Tibus skrev:
> Magnus and all,
> interestlingly the discussion about GMT seem to be a never ending 
> story, all over the world. As I know GMT was already renamed  in 
> the year 1925 ( or 1928 acc. other source ) to UT and 
> "universal time coordinated" (U T C) (that) is standard since 
> January 1, 1972. acc. "About the Time" :
> http://www.fai.org/astronautics/time.asp ,
> look into the short overview to this history. 
> "Does anyone know the exact difference between GMT and UTC?" 
> - this question seem to be already very old, Magnus. 

Um. That's not the question I am asking.

> Richard B. Langley wrote a summary trying to give the right 
> answer with "A Few Facts Concerning GMT, UT, and the RGO ". 
> His article can be found here:
> http://www.apparent-wind.com/gmt-explained.html 
> It summarizes:
> "The Greenwich mean time, GMT, has today only an historical 
> interest. It has been abandoned since the thirties for successively
>  the T U 1, the T U 2 and finally, in 1972, for the much more regular 
> universal time coordinated, U T C, that must be used 
> for all present use." ! 
> That is what I thought as well quite a while. 
> But I had to change ever so often all kind of scientific and 
> technical units, and I see the need to adopt it, I am sure we have 
> to be open for more steps into the future. Learning will never end...!

You brings me no new knowledge, only a few more links, which I suspect 
repeats what my sources already says to me.

I already know what GMT is in the several senses it is. For me it is 
clearly not UTC, except for the GMT transmissions done by BBC.

I object to the use of GMT when it should say UTC, they should not be 
used interchangeably when talking about international time.

The question I am asking is really about which is the time-scale 
accepted for national time in various countries.

So far:

UTC based: France, Sweden
GMT based (UT1?): Great Brittian, Denmark

I suspect several countries (such as US, Germany etc. etc) to be UTC 
based, but I do not know for sure.

As you see, this is a quite different question then asking about "what 
is GMT" or "what timezone is country X".


More information about the time-nuts mailing list