On 2010-02-09, David Woolley <[email protected]> wrote: > David J Taylor wrote: > >> I remember the flying of caesium or other atomic clocks round the world, >> and that folks had to invoke relativistic corrections. Were these >> better than microseconds as well?
The flying of clocks around maryland was primarily a test of the special relativistic corrections. For a distant sattelite, the General relativistic and special relativistic are essentially the same size ( because the speed of the sattelite is determined by the gravitational field of the earth). And both are in the PPB range-- and are cumulative(ie give a frequency shift to the clock rate. If it is a circular orbit that is it. If it is elliptical, then there is in addition a small periodic clock rate change. A PPB over an hour gives microsecond shifts in the time. > > That's called Navstar (GPS) and GPS position solutions do have to > include a general relativity correction to the satellite clocks. _______________________________________________ questions mailing list [email protected] http://lists.ntp.org/listinfo/questions
