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

On Mon, Mar 30, 2009 at 01:09:10PM EDT, Paul E Condon wrote:


> 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.

Rule Britannia.. Britannia rule the waves.. (?)

> 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.

Would that be Boulder, CO..? I vaguely remember that my "alarm clock"
sync's to its master over there, but I can't seem to get ahold of its
manual just now.

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

Fancy that.. under our latitudes, when your house is a few hundred yards
wide.. never mind.. I've overstayed my welcome on this here list.


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