At 13:06 15/04/99 , Ron Lee wrote: >I had a chance to see one of those in operation at Edwards AFB in 1977. >very impressive system. I would gladly take one or a smaller version >of the GEODDS optical tracking system. My current system is too >manpower intensive to provide lots of obs. I would be curious whether >my observations of high fliers is of sufficient accuracy to be useful. > >Can anyone here take an observation and determine residuals if elsets are >published? Ron, As I said in a separate reply, I would be glad to help, just wouldnt accept interference in current activities. Currently many CCD using amateur astronomers are doing routine asteroid observations with 25-45cm telescopes and getting residuals of under 1 arc second. the satellite problem is a timimg problem. The Baker-Nunn's used for satellite observation by the SAO programme had a residual error of about 4 arc seconds using film. The converted Baker-Nunn currently on siding spring mountain,( University of NSW automatic patrol telescope) with CCD detector has 9 arc second pixels, so could probably get 1 arc second accuracy in satellite astrometry if the timing can be solved. I know USAF hsd Rob McNaught do some tests for them using that scope. The Catalina Sky survey people at LPL have a CCD converted 18 inch schimdt which has a 2.9 degree field of view, and a 4000 by 4000 CCD. They use it for asteroid work but I guess it illustrates the possibilities. Since relative motion is about 15 arc seconds/ second, a timing accuracy of 0.2 seconds would imply corresponding positional errors of 3 arc seconds. One arc second at 40,000Km corresponds to about 200 meters. Tony Beresford