raduga decay

sbolton (sbolton@nbnet.nb.ca)
Tue, 20 Aug 1996 14:49:46 -0300

Having observed decay of Raduga 33 SL r2, some questions arise. This is the
first decay I've seen.

First a summary.  Observed from long - 66 W  Lat 45.5 N  ( Saint John, NB, Can)
Used 232.0247 elset from Allan Pickup and Satspy for predicted path through the
sky. The path was accurate within 5 seconds and approx 2 degrees. Passed
through bowl of big dipper at 00:47:00 UTC on Aug 20. The sat was at max
brightness, approx -2, just prior to U. Maj. and before reaching max
elevation above local horizon. Then appeared to slowly dim but remained
visible with binoculars and glowing to loss near the NE horizon.

Using the same elset in STSPLUS I plotted the sat for a few orbits. On the
orbit prior to the reentry I observed, Raduga reached a perigee of only 43.4
nm over the North Atlantic at lat 45.3  Long -46 W. Is this accurate, how
did it survive such a dip into thick air. Incidentally, this was in twlight
at sea- might it have been observed?

On the decay orbit (539) STSPLUS plots a path over the Baha Peninsula at 00:44,
altitude 140 nm. Path crossed over the central US, the terminator running
from E. Texas through the middle of Lake Superior. The sat was below 80 nm
once E. of the terminator. Perigee was predicted at 54 nm 00:50 UTC.

1. This event should have been widly observed from central Canada and NE US.
  Any other posts/ sightings ?

2. If the STSPLUS plots are correct, this object survived a very low pass on
the rev prior . Possible?- or is STSPLUS not reliable.

3. If it did survive the pass on rev 538- might the dimming I observed
represent the sat climbing out of dense atmosphere again? Raduga's next pass
was not attempted by me- but was favorible for N. A. observers.

Finally, for those not lucky enough to see a decay, keep trying -it is

                                                 Steve Bolton