STS 128 Ascent to ISS Trajectory Spreadsheet; MECO TLE

From: Ted Molczan (ssl3molcz@rogers.com)
Date: Tue Aug 25 2009 - 18:24:33 UTC

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    I have produced an MS Excel spreadsheet to compute azimuth, elevation, R.A. and
    Dec, and an indication whether the shuttle is in sunlight, or the umbra or
    penumbra of Earth's shadow, during STS 128's ascent to orbit on its mission to
    ISS:
    
    http://satobs.org/seesat_ref/Shuttle/STS_128_Ascent_Trajectory_to_ISS.xls
    
    To use, enter your observation site co-ordinates and the date and time of
    lift-off, in the specially labelled cells (those with red coloured font).
    
    The spreadsheet is set up for STS 128's scheduled launch on 2009 Aug 26 at
    05:10:23 UTC, as seen from Washington, D.C.
    
    I obtained the trajectory data from The CBS News Space Reporter's Handbook, by
    William Harwood:
    
    http://www.cbsnews.com/network/news/space/downloads.html
    
    Scroll down to the SpaceCalc section, and see file SpaceCalcPC_128.zip for PC or
    SpaceCalcMac_128.zip for Mac.
    
    For pre-launch TLEs (2-line elements), I recommend using NASA's web page:
    
    http://spaceflight1.nasa.gov/realdata/sightings/SSapplications/Post/JavaSSOP/orb
    it/SHUTTLE/SVPOST.html
    
    However, beware that on this web page, the MECO (main engine cut-off) elset, aka
    Coasting Arc #1, always is totally erroneous. NASA's conversion from state
    vector to TLE is set up to propagate the MECO elset to the next ascending node,
    even though the orbit will have been circularized well before then. The problem
    is exacerbated by the unrealistic treatment of orbital decay for this case. 
    
    Here is an alternative MECO TLE, computed from NASA's pre-launch state vector,
    using Ken Ernandes' VEC2TLE. It is valid until the circularization burn at about
    05:50 UTC:
    
    STS 128 MECO                                              59 X 234 km
    1 99128U          09238.22283981  .01000000  00000-0  54393-6 0    00
    2 99128  51.6389 307.4445 0134097 350.7048  67.1470 16.47403862    07
    
    VEC2TLE is available here:
    
    http://www.mindspring.com/~n2wwd/html/state_vectors.html
    
    Ted Molczan
    
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