AEHF 1 nearing the finish line

From: Ted Molczan (ssl3molcz@rogers.com)
Date: Sun Oct 16 2011 - 20:33:00 UTC

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    This is an update of my report of Aug 12, on the orbital evolution of AEHF 1 (10039A / 36868):
    
    http://satobs.org/seesat/Aug-2011/0076.html
    
    At the time, it was on track to achieve a 4.8 deg synchronous orbit about Oct 3rd; however, subsequent hobbyist tracking
    detected a one week hiatus from manoeuvring, beginning about Sep 13 UTC, after which they were smaller in magnitude.
    Spaceflight Now recently reported that the change is intended to "optimize fuel and extend the expected mission life of
    the satellite", and will delay arrival in synchronous orbit to late October 2011:
    
    http://www.spaceflightnow.com/atlas/av019/111009.html
    
    Mike McCants, who has led the hobbyist effort to track AEHF 1, currently estimates arrival in synchronous orbit about
    Oct 25. Last night, he and Peter Wakelin observed the object in a 4.5 deg, 35950 km x 36745 km orbit, with period 1464.8
    min.
    
    I have updated the plots of the evolution of the altitude, orbital period, and inclination since launch:
    
    http://satobs.org/seesat_ref/misc/AEHF_1_orbital_evolution_v2a.pdf
    
    For anyone interested in contributing to the tracking, I have appended the predicted orbit message Mike issued earlier
    today:
    
    Ted Molczan
    
    Peter Wakelin and I observed is last night.
    
    It brightened from magnitude 10 to about magnitude 5.5 as it flared just before going into the Earth's shadow last night
    about 1:45 UT.
    
    Here is the new elset:
    
    1 36868U 10039A   11289.10990407 0.00000000  00000-0  00000-0 0    08
    2 36868   4.4720 278.2095 0093000 238.9865 230.0000  0.98307000    08
    
    Predicted elsets:
    
    1 36868U 10039A   11289.47718779 0.00000000  00000-0  00000-0 0    08 35931
    2 36868   4.4621 278.2762 0083014 238.9320   0.0000  0.98517000    07
    1 36868U 10039A   11290.49224106 0.00000000  00000-0  00000-0 0    08 35918
    2 36868   4.4515 278.3282 0072038 238.9017   0.0000  0.98727000    07
    1 36868U 10039A   11291.50513522 0.00000000  00000-0  00000-0 0    04 35905
    2 36868   4.4406 278.3719 0061019 238.8849   0.0000  0.98937000    03
    
    The target date for longitude 80 west is approximately Oct 25.
    
    Use the tle preceding your time of prediction.
    
    The additional data on line 1 is the perigee height, which you may need to trim off, depending on your ephemeris
    generator.
    
    Mike
     
    
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