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AO-10 Keps




As many of you have noticed the NORAD Keps for AO-10 are well over 100 days
old and are showing their age.  Using ranging software (and hardware)
developed by James Miller for an Acorn RiscPC computer, I have made ranging
measurements on AO-10 for the last week and have fed these measurements
into an algorithm which generates modified Keplerian elements from a "seed"
set of elements.

The Keplerian elements below appear to be accurate within 16-25 km, as
opposed to the old, Day 207 NORAD keps, which are now over 650 km off in
accuracy at some points in the orbit.  These elements predicted this
evening's entry and exit of perigee eclipse to the minute, so I believe
they are considerably better than the older NORAD set.  More ranging
measurements are being obtained from different Phase 3 command stations,
and I will update these keps as those data become available.  In
particular, I do not know how inaccuracies in mean motion will affect these
keps over long periods of time, but for the moment they are more accurate
than what has been available.

Satellite: AO-10
Catalog number: 14129
Epoch time:      98317.89601
Inclination:        27.1180 deg
RA of node:         57.7960 deg
Eccentricity:     0.60017
Arg of perigee:    266.6020 deg
Mean anomaly:      216.3890 deg
Mean motion:     2.05834857 rev/day
Decay rate:         0.00e 0 rev/day^2

***Note that the Epoch time is "forward" set for almost 9/10ths of the way
through Friday 1998-Nov-12 (UTC), so until about 21:30 UTC today the MA may
appear as a negative number in your tracking program...it will revert to
normal after that time.  In the interim, the MA = 256-MA.




--  
 __________________________________________________________________________  
  Stacey E. Mills, W4SM    WWW: 	http://www.cstone.net/~w4sm/ham1.html 
   Charlottesville, VA	   PGP key:	http://www.cstone.net/~w4sm/key.asc    	
 __________________________________________________________________________


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