Tracking an unknown high altitude flasher
Ron Lee (ronlee@pcisys.net)
Sat, 18 Sep 1999 13:06:50 -0600
On 18 Sep 99 at about 03:20 UT I found my target stars for
an upcoming pass. Almost immediately I saw a bright flasher
about three degrees higher. It appeared relatively stationary
so I made a note of the time and location and waited for my
expected satellite. It never appeared (I never saw it!) so I
went in and ran Skymap with Mike McCants GEO.TLE file. To my
surprise nothing came close to matching.
I go back outside to see if it is still visible with the
intent of getting several positions/times. Armed with a Skymap
chart of the area, binoculars, stopwatch, red flashlight and
recliner, I look in the area to the east of the initial target
stars and indeed it is still visible.
So I decide to haul out the 8" telescope which required setting
up the electronic setting circles. Fortunately I am still able to
find it after another 15 minutes or so delay. It was apparent once
I got it in the scope that it was NOT a geosynchronous satellite.
It was moving too quickly to the east to be GEO. After dealing with
an equipment problem, I finally make my first semi-precise obs one
hour after first seeing it. I make two more observations in the next
16 minutes then go inside to make another star chart.
Going outside I determine about how far the satellite should have
moved and reposition the scope. Nothing in the eyepeiece. Nothing
around that spot. Nothing visible in the finder scope. Then I look
in the target area with binoculars. Nada. Scanning reveals nothing.
After 10 minutes or so I finally give up. Muttering under my breath
about losing something so easy to see in binoculars. Back to the
computer to run Skymap with a file of satellites in eccentric orbits.
AHA! a possible match. #23230 (ETS-6). Running it shows excellent
agreement with observed positions. The observed flash period around
11.5 seconds with approximate 3 and 8.x second intervals matched with
Ed's report.
Thus the mystery UNID was identified. Why did I go to such trouble
for a known flasher? At first, I thought it could have been a new GEO
flasher. Of course I was wrong about the orbit. I saw a probable
unknown high altitude flasher earlier this year that was never ID'ed.
So getting three or more positions would help nail it down.
Also earlier this year I saw an object that was likely an uncataloged
piece of an Ariane launch. But my positions were less that precise
so Mike was unable to define a suitable orbit. This episode just
reinforced my clumsiness at trying to get positions on a satellite
without knowing beforehand where it is going. But it was fun despite
the problems and clumsiness.
Ron Lee