Starshine 2 deployment TLE

Date: Thu Dec 06 2001 - 22:34:46 EST

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    When Starshine 1 was deployed, NASA had included its predicted deployment TLE 
    on their Realtime Date web page for the mission involved (I've forgotten 
    which STS number that was).  Using that TLE, along with the predicted shuttle 
    TLE in effect at the time, I found Starshine 1 should precede the shuttle by 
    about five degrees when they passed overhead here a few hours after 
    deployment.  Sure enough when they came by, there it was -- five degrees 
    infront, flashing once every 20-30 seconds or so.
    Unfortunately, this morning when I checked NASA's predicted shuttle TLEs, 
    there was no TLE for Starshine 2's deployment.  I wrote NASA's Jonathan 
    Weever to ask about it.  This is what I was told:
         [Jonathan Weaver]:
         I dont have the manual flexability that I used to regarding 
         posting additional deployement orbital elements, etc... 
         because we now use an automated Java script to build the 
         orbital elements ephemerides for the STS and the ISS.
         I would recommend the following: Based on the deployment 
         time for Starshine 2, just use the STS orbital elements file 
         which is closest in UTC time to the deployment time and that 
         will model the initial starshine deployment trajectory profile. 
         It will then be given a catalog number by USSPACECOMMAND, 
         and then you can get future TLE's for starshine from available 
    Taking his advice, I went to the NASA TV Schedule web page:
    There I found Starshine 2 is scheduled for deployment on orbit no. 153, 
    Saturday, Dec. 15, at 16:02 GMT.
    With that, I went to NASA's shuttle Realtime Date Orbital Elements page --
    -- to find the predicted shuttle TLE in effect for or preceding orbit 153.   
    That turned out to be orbit 139 (coasting arc #22): 
    SHUTTLE (Starshine 2 deployment)
    1 99108U          01348.79325464  .00071000  00000-0  10050-3 0  9215
    2 99108  51.6364 259.9170 0018465  94.2553 266.0713 15.60331700  1405  
    It happens the shuttle will do an orbit adjustment following the deployment 
    of Starshine 2, with Coasting Arc #23, beginning Orbit 154.  This has a 
    predicted TLE of 
    SHUTTLE (orbit 154, post deployment)
    1 99108U          01349.75392617  .00071000  00000-0  10050-3 0  9227
    2 99108  51.6359 255.0818 0018573  97.8471 262.4794 15.60398466  1550
    Using these two TLEs to model the passes of Starshine 2 and STS-108, 
    respectively, occurring later that evening, produced a gap between them of 
    under 1 degree, as viewed from my home in Maryland.   Unfortunately, from 
    here they would also barely skim 9 degrees above the NNW horizon.  
    However, assuming nominal deploy, those viewing from south of Hudson Bay 
    would see them pass through the zenith about 3 degrees apart.
    One concern with this, though, is that Starshine 1 was deployed downward, as 
    I recall.  In so doing, it orbited slight faster than the shuttle each 
    revolution.  Assuming this is the case with Starshine 2, I would expect the 
    gap between them, on the evening of Dec. 15th, would be wider than shown 
    using the two TLEs above.  How much wider, I can't say.   But since 
    deployment would have occurred only seven hours earlier, I would hope not a 
    great deal wider.
    [Questions:  Does anyone know what magnitude the Starshine 2 flashes may 
    reach?  Does anyone know how long after deployment US Space Command might 
    release its TLE for Starshine 2?]
    Clear skies, 
    Jim Cook
    Germantown, MD
    39.3N, 77.2W
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    This archive was generated by hypermail 2b29 : Thu Dec 06 2001 - 22:39:48 EST