Optical 07 Feb 2007

From: Greg Roberts (grr@telkomsa.net)
Date: Thu Feb 08 2007 - 08:26:49 EST

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    Observations 07 Feb 2006:
    ----------------------------
    
    Cosatrak 1 (Computerised satellite Tracking System).
    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.
    
    Used with 70mm focal length f/1.2 lens,integrating for 128 frames
    which is equivalent to a max exposure of 2.56 seconds per image.
    
    Site 0433 : Longitude 18.51294 deg East, Latitude  33.94058 deg S,
    Elevation 10 metres - situated in Pinelands (Cape Town), South Africa
    
    For CLASSIFIED.TLE:
    ------------------------
    
    90046 05 864A   0433 G 20070207182221900 56 15 0220030-255347 39  +075 05
    90046 05 864A   0433 G 20070207182434100 56 15 0229529-362235 39  +070 05
    90046 05 864A   0433 G 20070207182621500 56 15 0241204-463505 39  +070 05
    90046 05 864A   0433 G 20070207182821900 56 15 0303249-594340 39  +070 05
    90046 05 864A   0433 G 20070207183309600 56 15 1047284-804825 39  +075 05
    16591 86 014A   0433 G 20070207191621900 56 15 0700450-003344 39  +070 05
    16591 86 014A   0433 G 20070207191638600 56 15 0708402-032038 39  +070 05
    28888 05 042A   0433 G 20070207195122100 56 15 1323010-465145 39  +057 05
    28888 05 042A   0433 G 20070207195226800 56 15 1235476-414202 39  +055 05
    28888 05 042A   0433 G 20070207195311500 56 15 1202462-360521 39  +050 05
    
    Unknowns seen:
    -------------------
    
    91094 07 038LEO 0433 G 20070207191223300 56 15 0032249-513043 39  +075 05
    91094 07 038LEO 0433 G 20070207191223700 56 15 0032106-510248 39  +075 05
    91094 07 038LEO 0433 G 20070207191224100 56 15 0031586-503058 39  +075 05
    91094 07 038LEO 0433 G 20070207191224500 56 15 0032014-500108 39  +075 05
    91094 07 038LEO 0433 G 20070207191244900 56 15 0032021-493454 39  +075 05
    
    91095 07 038HEO 0433 G 20070207192608900 56 15 1644520-794341 39  +070 05
    91095 07 038HEO 0433 G 20070207192608600 56 15 1644424-794114 39  +080 05
    
    Strays seen:
    --------------
    
    SL-8 R/B  steady
    16864 86 052B   0433 G 20070207184634800 56 15 0243327+101422 39  +045 05
    Cosmos 1980 variable
    19649 88 102A   0433 G 20070207190822100 56 15 0053099-140104 39  +060 05
    Meteor 2-9 steady
    13718 82 116A   0433 G 20070207191251300 56 15 0004182-624634 39  +070 05
    Molniya 1-63 variable, range 4440 kilometres
    15429 84 124A   0433 G 20070207191849700 56 15 0714561-025342 39  +075 05
    Cosmos 1818  short period ~ 13 sec variable - pretty
    17369 87 011A   0433 G 20070207192735300 56 15 1535132-731626 39  +050 05
    Monitor-E/SL-19  slightly variable
    27840 03 031A   0433 G 20070207192817500 56 15 1609021-722547 39  +055 05
    M-5 R/B variable
    28942 06 005D   0433 G 20070207193452200 56 15 1329285-744908 39  +035 05
    Thor Ablestar rocket steady
    00669 63 038A   0433 G 20070207193635900 56 15 0930200-731918 39  +060 05
    Gorizont 17 geostationary, flashing about every 64 seconds
    19765 89 004A   0433 G 20070207195738500 56 15 0343368+100815 39  +035 05
    SL-8 R/B
    28381 04 028B   0433 G 20070207200033500 56 15 0400270+105030 39  +030 05
    Les 1  , irregular variable?
    01002 65 008C   0433 G 20070207200430600 56 15 0359256+114225 39  +050 05
    
    
    Notes:
    -------
    
    (1) Purpose was to test 70mm f/1.2 lens for geostationary survey work-
        concluded that it was useless. Lens is too fast for my city lit
        skies resulting in severe vignetting and a bright central field
        of view with low contrast. The electronic light control of the
        camera overode the instruction to integrate for 2.52 seconds and
        instead seemed to prefer a max integration time of about 0.4 secs.
        Stopping the lens down and increasing sky contrast/image quality
        might help by allowing increased exposure time but at the cost
        of a smaller aperture and hence lesser magnitude penetration.
    
    (2) The first unknown seen was a little difficult as it was moving
        the opposite way to which the camera was moving whilst tracking
        a leo satellite- this would make the satellite fainter. In
        addition the object appeared to be slightly variable making
        precise ends of the exposed trails difficult to determine exactly.
    
    (3) The second unknown only produced two points, sufficient to confirm
        that it was a satellite and direction in which moving. No further
        observations were possible as I moved the camera - only found the
        flashes when I was measuring. This will be an impossible one
        to find and positions given for "academic" interest.
    
    (4) Les 1 produced three flashes during the time observed. One was
        rather bright, followed 8.2 seconds later by a much weaker flash
        followed by a slightly brighter flash 2 seconds later.
    
    (5) I think Ill take a rest tonight whilst I think about what Im
        going to do next :-)))- besides its cloudy at the moment.
    
    
    Cheers
    Greg
    
    
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