Flaring geosats seen last night with small binoculars

From: Ed Cannon (ecannon@mail.utexas.edu)
Date: Sun Sep 25 2005 - 14:21:23 EDT

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    Flaring geosats seen last night (25 September UTC/24 September CDT) 
    using my handheld 8x42 binoculars:
    
    1. 25954, 99-060A, GE 4
    2. 28446, 04-041A, AMC 15
    3. 26038, 99-071A, Galaxy 11 (probable, based on past obs)
    4. 26624, 00-076A, Anik F1
    5. 23192, 94-047A, DirecTV 2 (DBS 2) or 25937, 99-056A, DirecTV 1R
    6. 26761, 01-018A, XM 1 (about 30 seconds west of XM 2)
    7. 27624, 01-012A, XM 2 (about 30 seconds east of XM 1)
    
    XM 1 and XM 2 were at least +7.5 and were visible about 1/8 degree
    apart from each other for quite a while.  I timed their separation
    with my stopwatch and twice got just over 31 seconds.  I can not
    determine which one was #5 above due to an imprecise time -- I
    wrote down only "3:50" -- no seconds.  Maybe the safer bet is the
    newer one?
    
    All of the above were seen at the "three hours early" position in
    the sky -- i.e., about three hours before shadow entry time.  This
    is about 45 degrees of sky before shadow entry.  I didn't see any
    at the actual shadow-entry position; it may still be a few nights 
    early for those.
    
    With the telescope Mike found two more very near GE 4.
    
    More information about "flaring geosats" (not to be confused with
    "flashing geosynchs").  I'll venture that "flaring" is due to 
    changing Sun-satellite-observer geometry, while "flashing" is due
    to a satellite rotating about its own axis either due to tumbling
    out of control or due to being spin-stabilized.  Also, flaring
    geosats are operational payloads, while flashing geosynchs are 
    not operational and most are not truly geosynchronous but are 
    slowly drifting around the world, over a period of months.
    
    LES 8 has now gone into twilight here.
    
    Ed Cannon - ecannon@mail.utexas.edu - Austin, Texas, USA
    
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