Obs 28th Dec 2004

From: Greg Roberts (grr@iafrica.com)
Date: Wed Dec 29 2004 - 11:53:48 EST

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    Observations 28 Dec 2004:
    ----------------------------
    
    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 82mm focal length f/1.6 lens with focal reducer,
    and showing 10th magnitude stars with a full moon around.
    
    Site 0433 : Longitude 18.51294 deg East, Latitude  33.94058 deg S,
    Elevation 10 metres - situated in Pinelands (Cape Town), South Africa
    
    Conditions good - moon later in evening caused no problems.
    
    28054 03 048A   0433 G 20041228183628400 17 15 0720100-363845 39
    28054 03 048A   0433 G 20041228183727000 17 15 0630274-234150 39
    28054 03 048A   0433 G 20041228183840900 17 15 0538338-034235 39
    25017 97 064A   0433 G 20041228185017200 17 15 2232424-180209 39
    25017 97 064A   0433 G 20041228185153000 17 15 2239090-571451 39
    25017 97 064A   0433 G 20041228185251900 17 15 2231100-814356 39
    26473 00 047A   0433 G 20041228190120600 17 15 2201114-204449 39
    26473 00 047A   0433 G 20041228190222100 17 15 2134011-394745 39
    26473 00 047A   0433 G 20041228190320900 17 15 2041512-570339 39
    21147 91 017A   0433 G 20041228192113600 17 15 2215055-343734 39
    21147 91 017A   0433 G 20041228192232900 17 15 2351563-122303 39
    21147 91 017A   0433 G 20041228192347200 17 15 0107523+125438 39
    90026 04 809A   0433 G 20041228190944900 17 15 0751278-381458 39
    90026 04 809A   0433 G 20041228191051500 17 15 0839320-412318 39
    90026 04 809A   0433 G 20041228191132500 17 15 0908125-422805 39
    23947 96 038C   0433 G 20041228193703400 17 15 0600310-635919 39
    23947 96 038C   0433 G 20041228194015400 17 15 0659043-561220 39
    23947 96 038C   0433 G 20041228194358100 17 15 0750327-435955 39
    27938 03 041B   0433 G 20041228195138600 17 15 0255431+062610 39
    27938 03 041B   0433 G 20041228195547800 17 15 0259531+062104 39+106 05
    13791 83 008A   0433 G 20041228201007400 17 15 2208342-542726 39
    13791 83 008A   0433 G 20041228201124200 17 15 2123182-651031 39
    13791 83 008A   0433 G 20041228201235900 17 15 1956565-724106 39
    13874 83 008H   0433 G 20041228202130900 17 15 2306127-411206 39
    13874 83 008H   0433 G 20041228202237500 17 15 2252011-513915 39
    13874 83 008H   0433 G 20041228202321000 17 15 2236477-582605 39
    13845 83 008F   0433 G 20041228203728400 17 15 2142371-644304 39
    13845 83 008F   0433 G 20041228203900500 17 15 1948046-731854 39
    22519 92 086C   0433 G 20041228204215100 17 15 0133488+070007 39
    22519 92 086C   0433 G 20041228204347300 17 15 0143283+025233 39
    25744 99 028A   0433 G 20041228210350500 17 15 1528195-734523 39
    25744 99 028A   0433 G 20041228210525200 17 15 1415157-693754 39
    25744 99 028A   0433 G 20041228210730600 17 15 1322504-622843 39
    22519 92 086C   0433 G 20041228212429000 17 15 0833008-650823 39
    22519 92 086C   0433 G 20041228212624600 17 15 0905123-644652 39
    
    Notes:
    
    (1) 2nd night spent experimenting with the new MINTRON. The views
        are tremendous and the video monitor filled with dozens of
        stars, generally going down to about magnitude +10. Besides
        tracking a few satellites I also did some astronomical viewing
        as well as getting images of the comet - still to process that.
    
    (2) All of the tracking - apart from the Lacrosse satellites - was
        done with the camera tracking on the satellite, so that the
        satellite appears as a star and the stars are trailed. At present
        it is rather time consuming to process these as I need to step
        through the video recorder frame by frame to get the time of the
        frame I decide to use - each frame is seperated by 2.54 seconds and
        it takes a lot of pressing of the VCR "pause" button to move through
        2.54 seconds of frames. This problem can be solved and I am currently
        thinking of capturing the video to pc for the pass required and then
        splitting the video into individual frames and then choose which to
        measure and extract the correct time. The measuring itself is very
        quick.
    
    (3) Maybe I am too tired today from a late night last night but sometimes
        it may have happened that I measured the wrong end of the star trail.
    
        Those brighter than me might like to think of the problem:
    
         -- the satellite is descending on a pass and the camera is tracking
         on the satellite so that as the satellite drops in elevation stars
         appear to be moving upwards on the video monitor. Every 2.54 seconds
         a new image is displayed, so the star trail is 2.54 seconds long.
         When the new image is displayed I note the time displayed on the video
         monitor. Now which end of the star trail corresponds to the position
         at that instant ?
    
         Now what happens when the satellite is ascending so that the stars
         then move downwards - which end of the trail is the one I want ?
    
         I hope I did things correctly when I measured but at the moment I
         cannot think straight!- ( what can one expect from a senile bald
         header crock?) - my apologies to the orbit analysts if I messed up.
    
    (4)  After trying for USA125 Rk 2 #23947 for the past few weeks I finally
         got it by tracking on it -- it was easy!  The same goes for the NOSS
         objects - normally I ignore the older NOSS satellites if the predicted
         magnitude is greater than +9 or,so or poorly positioned in the sky-
         by tracking on the satellite I had no trouble following them above
         an elevation of (say) 20 degrees. Only Noss 4(F) disappeared from
         view.
    
    (5)  USA 171 Rocket was another satellite I previously could not see -
         this was very faint and estimated at about magnitude +10.6. Since
         the integration mode was on and the satellite essentially geostationary
         the satellites and stars were integrated equally so I could determine
         magnitude. Visually I could see stars down to about +11 on the monitor.
    
    (6)  USA 89 rocket (#22519) was the most difficult customer - even when
         tracking on it it was only visible for a few seconds over a period
         of minutes so most of the time I was tracking blind on predictions.
    
    (7)  At the end of the session I had a look at the predicted position
         of #15071 KH9-19 but as it had not been observed for over 80 days
         and the elevation was about 15 degrees I decided to just sit and
         look at the area, starting about 5 minutes early to about 10 minutes
         after pass time. I did not see it so guess that if it passed over
         then it was fainter than magnitude +8 or so.
    
         Several other satellites were seen during this time and identified:
    
         90010A - #20465 Cosmos 2058 - predicted magnitude +6.9
         84027B - #14820 Cosmos 1544 rocket - predicted mag +7.0 but was fainter
         84106A - #15333 Cosmos 1603 - predicted +7.5, but brighter
         85100B - #16194 Meteor 3-1 rocket - predicted +8.3 and was barely visible.
         and finally an interesting one:
         90045B - #20620 Cosmos 2080 - at a range of 23000 kms and varying in
         magnitude from about +4.2 to invisible, but visible for most of its
         period. This is a Glonass satellite in a circular orbit and probably
         worth looking at if you want to see a slow moving satellite.
    
     (8) Thats all, to which all heave a sigh of relief - I wont be tracking
         again for the next 4-5 days as I want to make some other changes etc
         and try and speed up the processing routine. It took me the whole day
         today!
    
    Cheers
    Happy New Year to all
    Greg
    
     
    
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