NROL-1 estimated parking and transfer orbits

From: Ted Molczan (molczan@rogers.com)
Date: Fri Aug 27 2004 - 15:15:34 EDT

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    Here are a couple of possible parking orbits, assuming launch on 2004 Aug 27 at
    23:06 UTC:
    
                                                                191 X 323
    1 72000U          04241.01012732  .00000000  00000-0  00000-0 0    09
    2 72000  58.4289 226.6574 0100000  55.0000 235.6815 16.08708850    03
                                                                193 X 416
    1 72000U          04241.01012731  .00000000  00000-0  00000-0 0    08
    2 72000  58.4281 226.6613 0167000 110.0637 179.6650 15.91566646    00
    
    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          04241.01012733  .00000000  00000-0  00000-0 0    00
    2 72000  58.4281 226.6613 7445000 290.0637   0.0000  2.00600000    00
    
    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.
    
    There is a strong probability that today's launch will be delayed due to bad
    weather. Tomorrow's forecast is worse. 
    
    The launch window is planar; I expect it to arrive about 4.6 min earlier per day
    of any launch delay.
    
    Ted Molczan
    
    
    
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