Trail of unknown object on CCD image

From: Paolo (xberardi@tin.it)
Date: Tue Jan 10 2006 - 18:59:14 EST

  • Next message: Matson, Robert: "RE: Trail of unknown object on CCD image"

    Hi all!
    This is my first post here. I'm looking for satellite observational
    site/forum after having noted an unknown trail on my astronomical photo with
    CCD camera.
    
    Yes, my main interest is astro-imaging. I'm an amateur astronomer living in
    L'Aquila, a small town close to centre of Italy. I consider satellite
    observation a fascinating activity too. Moreover, sometimes activities
    "crossing" are inevitable! Just like what is happened a few days ago.
    
    Following a CCD camera recent purchase, I begin a survey principally for
    test the new equipment, a Starlight Xpress SXV-H9 CCD camera (a very
    sensitive camera) with a Pentax astrograph (500 mm focal lenght).
    
    I find a mysterious trail on two photos of the Great Nebula of Orion (code
    Messier 42). Both trails direction are on the same alignment, therefore it
    seems that the object show a change of position between first and the second
    shot. This is the reason to exclude cosmic rays cause (CCD cameras are very
    sensitive to cosmic rays, resulting in a trail when they strike the CCD
    image sensor at glancing angles).
    
    A peculiarity is the relative low angular speed. I find approx 7'/minute
    (about 1/8 of degree per minute). Then the unknown object is too slow
    compared to an usual satellite (low orbit type) or an airplane, too fast
    compared to an asteroid or a so faint comet.
    
    Another important observation: on the basis of simple geometric
    calculations, I find the object had to be at least 15000 Km from earth
    surface so that it's outside earth shadow and the sun can light up it. In
    fact the observation time was at about 00:45 local time (unusual moment for
    common visual satellite) and the object was at about 40 degree above horizon
    toward south azimuth.
    
    Then, what is the object? I think about high altitude satellite in highly
    eccentric orbits or geosynchronous transfer orbits (GTO) or mid earth orbit,
    etc.
    
    Furthermore I read about several satellite launch on 21 december, the same
    day of my observations. Here is a list:
    
      COSPAR/WWAS USSTRATCOM  SPACECRAFT              LAUNCH
        INT.ID    CAT. #      NAME                   DATE (UT)
      ----------------------------------------------------------------
       2005-049B    28912    MSG 2                 21 December 2005
       2005-049A    28911    INSAT 4A              21 December 2005
       2005-048B    28909    Rodnik                21 December 2005
       2005-048A    28908    Gonets-D1M 1          21 December 2005
       2005-047A    28906    Progress-M 55         21 December 2005
    
    May be a Rocket in transfer orbit?
    
    I submit this questions to you, I think this is the best place to find an
    answer! Meanwhile I request an account at Space-Track to retrieve global TLE
    for simulations.
    
    Follow all related observational informations:
    
    Site coordinate
    City: L'Aquila, Italy
    Long.: 13 24' 24" EAST
    Lat.: 42 20' 05" NORTH
    Altitude: 700 meters over sea level
    
    Photo #2 (complete trail)
    Date: 21 december 2005
    Time: U.T. from 23h:45m:46s to 23h:47m:46s (precision +/- 3 sec)
    Total exposure time: 120 sec
    
    Photo #1 (incomplete trail)
    Date: 21 december 2005
    Time: U.T. from 23h:43m:38s to 23h:44m:38s (precision +/- 3 sec)
    Total exposure time: 60 sec
    
    I find equatorial and azimutal coordinates (RA, Dec, Alt, Azim) for a
    specific moment, thanks to the trail crossing over a note star. Star is
    named SAO 132323 (visual star of apparent magnitude 2.75):
    
    Right Ascension (RA2000): 5h 35m 26s
    Declination (Dec2000): -5 54' 36"
    Crossing time: U.T. 23h:46m:30s
    Alt. at crossing time: + 39
    Azim. at crossing time: 200
    
    I don't know the object apparent magnitude, but the CCD sensor is very
    sensitive, then certainly it's not a very bright satellite.
    
    This is the link to my photos, so you can estimate brightness and other
    feature of the trail:
    
    http://www.acvaquila.it/app/sat_track_aq.jpg
    
    I Hope this is not an off-topic argument and you find it to be to your
    liking. Waiting for good news!
    
    Best regards and clear sky!
    Paolo
    
    PS: sorry for bad english...
    
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