Shenzhou 7 pre-launch estimated elements

From: Ted Molczan (ssl3molcz@rogers.com)
Date: Mon Sep 15 2008 - 18:54:24 UTC

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    There have been several news reports that Shenzhou 7 will be launched on 2008
    Sep 25 at 09:10 PM CST (China Standard Time), which is 13:10 UTC. If correct,
    this would result in passes over Beijing in late afternoon and early evening. My
    guess is that the EVA is planned to be in progress during one of the late
    afternoon passes.
    
    Roughly speaking, northern hemisphere satellite observers would have evening
    visibility; the southern hemisphere would have morning visibility. Please use
    the estimated elements to determine your observing prospects.
    
    The following search elements are based on the assumption that the orbits
    employed will be the same as those of Shenzhous 5 and 6.
    
    1. Shenzhou 7 
    
    1.1 Elliptical parking orbit until 2008 Sep 25 at 20:03 UTC
    
    Shenzhou 7 will enter an elliptical parking orbit, in which it will remain for
    the first approx 6 h and 53 m after launch. I suggest the following elements:
    
    Shenzhou 7       7.8  2.5  0.0  5.4 d                    198 X 339 km
    1 70700U 70700A   08269.59627480  .00794136  00000-0  60000-3 0    06
    2 70700  42.4153 193.9946 0106040 130.0626 230.9292 16.02866600    07
    
    While in its parking orbit, Shenzhou 7 will trail a short distance behind its
    rocket body. Elements of the rocket body are in Section 2.
    
    1.2 Circularized orbit after 2008 Sep 25 at 20:03 UTC
    
    Shenzhous 1, 3, 4 and 5 manoeuvred to raise their perigee as they passed through
    apogee for the 5th time. Shenzhou 1 raised its perigee by only 8 km; Shenzhous
    3, 4, 5 and 6 raised it more than 130 km, to nearly circularize their orbit, and
    I expect Shenzhou 7 to do the same. Approx 6 h and 53 m after launch, Shenzhou 7
    should be in this orbit:
    
    Shenzhou 7       7.8  2.5  0.0  5.4 d                    335 X 338 km
    1 70700U 70700A   08269.84544062  .00000000  00000-0  00000-0 0    09
    2 70700  42.4207 192.3954 0002833 248.3475 111.7085 15.78579562    05
    
    Note that the zero decay terms of the circularized Shenzhou elements are
    intentional; past missions made a number of small manoeuvres throughout their
    flight, that essentially negated the effects of drag, apparently to achieve a
    nearly exactly repeating ground track every 31 revolutions.
    
    2. Rocket Body
    
    I suggest the following elements for the 2nd stage rocket:
    
    Shenzhou 7 r    15.5  3.4  0.0  4.4 d                    198 X 334 km
    1 70701U 70700B   08269.59626106  .00809611  00000-0  60000-3 0    06
    2 70701  42.4153 193.9946 0102545 130.0626 230.9292 16.03716253    03
    
    Note that as a result of its separation manoeuvre upon orbital insertion, the
    rocket's apogee will be nearly 5 km lower than that of Shenzhou's parking orbit;
    therefore, Shenzhou will trail a short distance behind its rocket body, until it
    circularizes its orbit, about 6 h and 53 m after launch.
    
    Ted Molczan
    
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