Obs 24 Nov 2005 (Zone 1 and 2)

From: Greg Roberts (grr@iafrica.com)
Date: Fri Nov 25 2005 - 11:57:15 EST

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    Observations 24 Nov 2005:( Zone 1 and 2)
    -----------------------------------------------
    
    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 145mm focal length f/2.5 lens,integrating for 96 frames
    which is equivalent to an exposure of 1.92 seconds per image,field
    of view 2.50 deg x 1.86 degrees.
    
    Site 0433 : Longitude 18.51294 deg East, Latitude  33.94058 deg S,
    Elevation 10 metres - situated in Pinelands (Cape Town), South Africa
    
    Unknowns:
    -------------
    
    91043 05 338GEO 0433 G 20051124195206300 56 15 0414414+042036 39  +100 05
    91043 05 338GEO 0433 G 20051124195230800 56 15 0415071+042110 39  +100 05
    91043 05 338GEO 0433 G 20051124195255300 56 15 0415347+042124 39  +100 05
    
    91044 05 338GEO 0433 G 20051124195721800 56 15 0402203+054830 39  +105 05
    91044 05 338GEO 0433 G 20051124195853800 56 15 0403541+055024 39  +105 05
    
    
    Notes:
    ------
    
    (1) I have decided to do another survey of the area where most geostationary
        satellites hang out,starting in the east as soon as its completely dark
        and slowly working over to the west.This is going to take many nights
        to complete as its slow and I will have to repeat some areas where I
        found something interesting. So far I have examined two scanned areas
        as follows:
    
        Zone 1: Az 059 to 065 degrees, stepping in 2 degree increments and
                El 24 to 28.5 degrees, stepping in 1.5 degree increments.
    
                It is basically a box search and the camera mount is set on
                az 059 deg and elevation 24 deg and watches the area for 90
                seconds before changing azimuth to 061 degrees and still at
                elevation 24.
    
                After azimuth 065, elev 24 degrees has been done the mount
                then goes back to azimuth 059 but increases elevation to 25.5
                degrees and so on. Of course this is all computer controlled
                and the observer does not have to be present.
    
        Zone 2: Az 045 to 055 degrees, elevation 26 to 35 degrees. Same
                routine as for Zone 1.
    
    (2) These two areas produced a total of 26 satellites, some of which were
        LEO or MEO satellites. I will report all in due course.
    
    (3) The basic integration time for each image is about 1.92 seconds and
        stars /geo satellites down to magnitude 11 are obvious. Images of the
        same area are then stacked to give an effective exposure of about 1
        minute and this shows geostationary satellites down to about
        magnitude 13.
    
        Unfortunately a lot of CCD chip defects are apparent and despite
        doing a darkframe to remove the defects, many still remain so I
        am ignoring anything fainter than about 12th magnitude. This is a
        problem I have not yet really solved.
    
    (4) Last night I did the first 5 zones but its taken me most of today to
        go through zone 1 and 2 so guess what I will be doing this weekend:-))
    
    (5) I have yet to go through these two areas and look for flashing
        geostationary satellites which do not integrate well.
    
    (6) I am reasonably confident that the two unknowns reported are "real"
        but it will require more observations to get meaningful orbits.
    
    
    Cheers
    Greg
    
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