Optical 24 Dec 2008 Part 1

From: Greg Roberts (grr@telkomsa.net)
Date: Thu Dec 25 2008 - 13:43:15 UTC

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    Observations 24 Dec 2008 Part 1
    -------------------------------------
    
    Cosatrak 1 (Computerised satellite Tracking System).
    Camera mount now carries two systems that can be operated
    together as two totally different sytems and computers used.
    Generally the DSI Pro II camera will be used for high altitude
    slow moving objects. Tests seem to indicate that its sensitivity
    is comparable to the MINTRON ( possibly better) but as its not
    possible (?) to time stamp to better than 1 second accuracy the
    time resolution is not good enough for LEO objects.
    
    
    (2)Meade DSI Pro II Monochrome CCD camera without filters.
    using integration times of 20 sec min to 60 seconds maximum
    depending on brightness of sky in particular area.No image
    processing done but dark field applied.
    Used with 200mm focal length f/2.8 Nikkon telephoto lens,
    field of view 1.88 x 1.40 degrees. Can get to magnitude 13
    or so in less than 20 seconds exposure.
    Exposure time to nearest second inserted into image FITS header
    from PC clock which is automatically checked every minute against
    GPS signal.
    
    Site 0433 : Longitude 18.51294 deg East, Latitude -33.94058 deg,
    Elevation 10 metres-situated in Pinelands (Cape Town),South Africa
    
    
    UNKNOWN 1:
    ------------------- 
    91133 08 860A   0433 E 20081224223551000 56 15 0848566+052223 39  +110 05
    91133 08 860A   0433 E 20081224223633000 56 15 0849383+052210 39  +110 05
    
    UNKNOWN 2:
    ---------------------
    91134 08 860B   0433 E 20081224223551000 56 15 0849331+052242 39  +105 05
    91134 08 860B   0433 E 20081224223633000 56 15 0850151+052248 39  +105 05
    
    UNKNOWN 3:
    -----------
    91135 08 860C   0433 E 20081224224438000 56 15 0827257+053721 39  +090 05
    91135 08 860C   0433 E 20081224224518000 56 15 0827238+053941 39  +090 05
    91135 08 860C   0433 E 20081224224520000 56 15 0828066+053936 39  +090 05
    91135 08 860C   0433 E 20081224224600000 56 15 0828051+054203 39  +090 05
    
    Notes:
    --------
    
    (1) Im testing a new tracking approach for myself in locating unknown
        satellites and spent 7 hours on testing it last night. I still have
        a large number of images to go through - probably take me another 2-3
        days to examine them all, but already found three satellites that do
        not have a match to anything in my database at this stage.
    
    (2) #91133 and #91134 are geostationary satellites close to one another
        and quite bright and steady. #91135 is a slow moving object so is
        probably some large piece of debri-probably a rocket in a GTO orbit.
        It was quite bright and steady during the period it was imaged.
    
    I do not expect to recover all unknown objects as the observed arc is too
    small but some of them - especially the geo sats - will probably be in
    the same position or close by and will enable a good orbit to be
    determined.
    
    Back to measuring!
    Cheers
    Greg 
    
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