From: [EMAIL PROTECTED] (Tim Shoppa) Subject: Re: [time-nuts] List of time synchronization hardware and software Date: Tue, 17 Jan 2006 17:20:40 -0500 Message-ID: <[EMAIL PROTECTED]>
> "Poul-Henning Kamp" <[EMAIL PROTECTED]> wrote: > > Pulsars were considered for timekeeping several times in the past, and in > > every instance the winning argument was "You want to base our timekeeping > > on some cosmic phenomena we don't even know what is ?". > > Well, look at how dependent NTP and navigation and telecommunications > is on GPS sats today. There the uncertainty isn't the technology but > the military/government/funding/infrastructure behind them. Glonass > helps, as will Galileo. I'm a little surprised there aren't more > Glonass receivers out there (they seemed confined to a segment of > the surveying population although maybe my view isn't quite as global > as it should be.) > > The threat isn't quite as big as the funding to the IERS = International > Earth Rotation Service. Cut off their budget and the earth may stop > turning, it's almost as bad as the Philosopher's Union! > > Seafarers happily used astronomical fixes (along with a good > chronometer) for many years long before we understood stellar dynamics. > Full understanding of a phenomena is hardly necessary to use it as > part of a tool. That said, I think we understand pulsars a little > better than we did at first discovery (where the LGM hypothesis seemed > to stand out...) Eeeeehum... have we been able to separate the time meredian from the navigational meredian such that a free-drifting UTC will not affect the ability to navigate? I surely hope so, or we will have a big problem here... I don't know the details, but it is reasnoble that the GPS reference stations positions in WGS-84 will keep the GPS coordinate system locked correctly. Time to read-up on the WGS-84 coordinate system and its relations to time- scales again. They do relate one way or the other. Cheers, Magnus _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
