Optical 04 Jan 2009-part 1

From: Greg Roberts (grr@telkomsa.net)
Date: Mon Jan 05 2009 - 14:43:02 UTC

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    Observations 04 Jan 2009
    ------------------------------
    
    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.
    
    (1) 145mm focal length f/2.5 lens fitted to MINTRON low light
    level CCD surveillance camera (0.005 lux typical in non integration
    mode) and 0.00005 lux in STARLIGHT mode with 128 frame integration.
    Image integrated for 2.56 seconds but exposure depends on sky background
    brightness. Field of view 2.5 x 1.9 degrees and showing about mag +12
    stars in "real time". Used as a finder for the 6 inch reflector.
    Individual frames are video time stamped with GPS derived signal.
    
    (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.
    Used with 6 inch f/5 CELESTRON reflector modified to f/2.7 with home
    made corrector lens.Field of view 55 by 40 arc minutes and showing
    15th magnitude stars in real time.
    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
    
    BRIGHT UNKNOWN?
    ------------------------------
    91139 09 505A   0433 G 20090104212005600 56 15 0529571+044304 39  +030 05
    91139 09 505A   0433 G 20090104212018400 56 15 0535137+045204 39  +030 05
    91139 09 505A   0433 G 20090104212026000 56 15 0538217+045754 39  +030 05
    
    Could this be another observation of Unknown 91137-details below:
    
    91137 08 859LEO 0433 E 20081224185123300 56 15 0256530+065202 39  +035 05
    91137 08 859LEO 0433 E 20081224185130500 56 15 0304560+061433 39  +035 05
    91137 08 859LEO 0433 E 20081224185136900 56 15 0311540+053957 39  +035 05
    91137 08 859LEO 0433 E 20081224185145700 56 15 0321170+045704 39  +035 05
    
    Notes:-
    ----------
    
    (1) Bright unknown in low inclination (~ 30 degree orbit). May be another
         observation of unknown 91137 done on 24 Dec 2008? Probably object in
         GTO orbit doing near perigee pass.
    
    (2) I will have to report the other observations made tomorrow as I have run out 
    of
         time for today and want to observe again tonight. Dont ask when Im going to 
    do
         the satellites observed on 03 Jan 2009 with the video system....
    
    Cheers
    Greg
    
    
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