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Re: To synchronize system time witn NTP-server with no winter time shift whole year - how to?

On 2009-03-30_09:41:58, Tzafrir Cohen wrote:
> On Sun, Mar 29, 2009 at 10:13:12PM -0500, John Hasler wrote:
> > Paul E Condon writes:
> > > The current standard is better described as a de-jure standard, IMHO.
> > > Didn't Congress pass a law on this issue? 
> > 
> > Of course.  Otherwise we might have people doing things without
> > permission.  Everything _must_ be regulated, after all.
> Sure. Why not use a time zone based on the exact spot where you live?

FYI. GMT definition is based on an exact spot with in the campus of
the old Greenwich Observatory (which has now been decommissioned).
Telescopes to the east or the west of that spot by about 289 meters
have local time that is 1s different from GMT. I don't know whether
there was ever a telescope at the exact spot that has been used as
reference. Astronomers knew how to make corrections for differing
locations of telescopes well before Greenwich became the consensus
reference location. The exact spot may have been selected with some
intent to please a royal person. It was because they new how to make
corrections that it became valuable to select a common reference
point. The early French referenced a meridian that was some number of
degrees minutes and seconds of arc to the west of Paris. They never
mentioned Greenwich, but their reference meridian happened to be the
one on which Greenwich was located. Strange accident? I think not.

Most astronomical observatories do have a clock set to local time and
the astronomers think nothing of it. They would be seriously put out
if local authorities wanted them to set that clock to standard or
daylight time.

This astronomical work has all been done to a precision that is vastly
greater than my personal needs. I live within 6 minutes of arc of the
105 west meridian. I can live with using local time on that meridian.

But "exact spot"? That would imply different clock settings in
different rooms of one's home. Not for me.

Paul E Condon           

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