Elements 71110C

Greg Roberts (grr@da.saao.ac.za)
Fri, 17 Jan 1997 11:38:19 +0200

Goodday see-saters,

About two months ago I posted elements,based on radio observations,for
the long lost classified object 71110C requesting possible visual
confirmation. Since then the orbit has been further refined and has now
been providing good predictions for radio tracking, with AOS (acquisition
of signal),TCA ( time closest approach - ie max elevation) and LOS (loss
of signal) with an error less than 1 minute. During a spell of night
visibility possible sightings were obtained by myself and Raoul Behrend
of the Geneva Observatory who has been working with me on this project.
In my case everything matched except that the time error for the visual
observation did not agree ( about 25 seconds difference) with the radio
error. In Raouls case he lost the time/position information when his tape
recorder froze because of the freezing weather! Intensive searches by both
Raoul and myself have established that the satellite is NOT a binocular
object ( ie 7x50's for example ) and at brightest is only about magnitude
8 and probably being about magnitude 9-10 most of the rest of the time.

The elements below, deduced by Raoul using his doppler analysis program 
and more than 1000 doppler readings over a period of three months,had a
radio observed error yesterday with the satellite running slightly late
but within a minute error.

The satellite transmits a continuous carrier on 137.080 MHz but only when
in sunlight. Raouls analysis showed that the satellite transmitter started
transmitting 24 seconds after it had cleared the earths shadow.

DOD
1 05680U 71110C   96359.13289350  .00000000  00000-0  00000-0 0    27
2 05680  70.0000 246.2020 0000001   0.0000 317.7030 13.73819268    15

We have now virtually exhausted the use of radio doppler observations to
refine the orbit further and to really tie down the orbit optical observations
are necessary. The eccentricity is very small and the inclination is probably
a little less than 70.0 by perhaps as much as 0.1 degrees,but otherwise it
is felt the orbit is good enough for optical work.

My thanks to Raoul for all the hard work he has done with the analysis - what
would we do without e-mail!

Good luck
Greg