NROL-1 estimated parking and transfer orbits

From: Ted Molczan (molczan@rogers.com)
Date: Tue Aug 31 2004 - 19:29:45 EDT

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    Here are updates of my parking orbit guesses, based on the launch that took
    place on 2004 Aug 31 at 23:17 UTC (the very end of a launch window that opened
    at 22:49 UTC):
    
                                                                191 X 323
    1 72000U          04245.01776620  .00000000  00000-0  00000-0 0    06
    2 72000  58.4289 233.3575 0100000  55.0000 235.6815 16.08708850    09
                                                                193 X 416
    1 72000U          04245.01776620  .00000000  00000-0  00000-0 0    06
    2 72000  58.4281 233.3614 0167000 110.0637 179.6650 15.91566646    06
    
    The first assumes that perigee occurs near the point of Centaur MECO1 (Main
    Engine Cut-off #1), i.e. orbital insertion; the second assumes that apogee
    occurs near Centaur MES2 (Main Engine Start #2), the start of the Centaur's
    second and final burn.
    
    The epoch of both corresponds to MES2, 68 min 35 s after launch, which I believe
    will result in a transfer orbit to a Molniya orbit, very roughly like this:
    
                                                              414 X 39957
    1 72000U          04245.01776620  .00000000  00000-0  00000-0 0    06
    2 72000  58.4281 233.3614 7445000 290.0637   0.0000  2.00600000    06
    
    I expect the payload to manoeuvre at high altitude to change the inclination to
    approximately 63.4 deg, which will also change the RAAN. Also, I suspect that
    the final argument of perigee will be closer to 270 deg than 290 deg, but I do
    not know which manoeuvre would bring that about.
    
    Ted Molczan
    
    
    
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