Observations 28 Apr 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 100mm focal length f/2.8 lens,integrating for 96 frames
which is equivalent to an exposure of 1.92 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 CLASSFD.TLE:
==================
14728 84 012C 0433 G 20060428171047200 56 15 1043541+231023 39 +100 05
14728 84 012C 0433 G 20060428171158600 56 15 1106558+151637 39 +090 05
14728 84 012C 0433 G 20060428171253100 56 15 1126147+083949 39 +085 05
14728 84 012C 0433 G 20060428171358900 56 15 1151344+001127 39 +080 05
28636 05 011A 0433 G 20060428172506500 56 15 0300385-591708 39 +090 05
28636 05 011A 0433 G 20060428172612300 56 15 0413103-422043 39 +090 05
28636 05 011A 0433 G 20060428172733100 56 15 0458142-164647 39 +090 05
28636 05 011A 0433 G 20060428172829500 56 15 0515088-010328 39 +095 05
28636 05 011A 0433 G 20060428172927800 56 15 0526005+114042 39 +100 05
28637 05 011B 0433 G 20060428173407900 56 15 0308299-311108 39 +085 05
28637 05 011B 0433 G 20060428173525000 56 15 0340308-173505 39 +090 05
28637 05 011B 0433 G 20060428173634600 56 15 0400172-055043 39 +095 05
90020 04 539A 0433 G 20060428174436200 56 15 0414243-100608 39 +090 05
90020 04 539A 0433 G 20060428174632800 56 15 0413292-154502 39 +070 05
90020 04 539A 0433 G 20060428174906900 56 15 0410006-244539 39 +075 05
90020 04 539A 0433 G 20060428175120400 56 15 0403203-341647 39 +065 05
90020 04 539A 0433 G 20060428175445300 56 15 0337067-522006 39 +065 05
Stray:
======
Meteor 1-11 rocket
05918 72 022B 0433 G 20060428172154700 56 15 0210186-644322 39 +060 05
Notes:
=======
(1) Many thanks to Ted for identifying unknown #91061 as XSS-11.The
orbit he produced was "spot on". All I had to do was point the CCD
camera at the predicted position and start it tracking "blind" ( ie
I could not see the satellite on the monitor screen) and as soon as
it started tracking on the predicted position the satellite was
immediately seen and I was able to follow it until it went behind
my neighbours house. Not an easy satellite as it is quite variable.
Max elevation was about 30 degrees.
When tracking on a predicted position the camera is effectively
doing a time exposure - since the system is tracking on the
satellite, the satellite is effectively "stationary" in the field
of view and one thus gains another 2-3 magnitudes, making it
possible to track satellites not visible in "real time" - ie seen
on the monitor. Since the system is tracking on the satellite the
stars appear to be moving and produced trailed images.
Another advantage of using time exposures in visual tracking is
that one has a trail that is a function of the exposure length
and angular velocity at which the camera is tracking so one can
determine the range to the satellite quite accurately. The trail
produced also allows one to determine the "track angle" which
is related to the satellite orbital inclination.
One might ask "how do you know the time of the exposure of a
trailed image". In my case I have a real time display of time,down
to a resolution of 0.1 seconds, that is displayed on the screen
and superimposed on the video image from the camera. If I am (say)
integrating ( exposing) for 96 frames ( equivalent to 1.92 seconds)
the image on the screen is "updated" every 1.92 seconds, so at the
instant the image is updated I make a note of the time shown on
the screen.Depending on the direction of motion of the camera will
enable you to decide which end of the trail is the position you
want. Obviously you can get two times and positions from one trail
since you know the exposure length.
Note: users in the USA ( for example) have a different TV video
system to what I have. Mine is known as PAL and the video frame
rate is 1/50th second. In the USA the TV system used is NTSC and
this has a frame rate of 1/60th second, so for a USA system the
96 frame integration is 96/60 = 1.60 seconds, whereas mine is
96/50 = 1.92 seconds.
The reason Ive mentioned all this is that I get frequent requests
from readers for an explanation of the terminology used and how
one goes about doing it.
If there are no objections I would be happy to give a short
discourse on SeeSat from time to time on various subjects related
to using video techniques for satellite tracking.
(2) XSS-11 rocket was more difficult- the maximum elevation was only about
12 degrees and showed more variability than XSS-11 although its short
flashes were sometimes brighter than any produced by XSS-11.
(3) Stopped by cloud after #90020.
Cheers
Greg
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