96 29A & C obs report, June 9, 1996

Mike McCants (mike@comshare.com)
Sun, 9 Jun 1996 13:59:51 -0500

We watched 96 29A and C for about 10 minutes on a zenith pass last night.
The pair was acquired at an altitude of 30 degrees in the south about
3:47UT June 9 and we stopped watching them low in the north about 3:57UT.

Object 96 29C was leading by about 8 to 10 seconds.  It seemed to be on time
compared to the following elset.  It was "uninteresting" (compared to 96 29A)
because it was steady in brightness.

NOSS 2-3 (C)  
1 96293U 96029  C 96160.03401779 0.00000400  00000-0  71797-3 0    03
2 96293  63.4199 202.2406 0077004 182.8327 177.1673 13.40264515    03

96 29C seems to be in a stable orbit, but a "drag" term of 0.00000400
is too high compared to other NOSS payloads.

Here is my elset for 96 29A:

NOSS 2-3 (A)  
1 23862U 96029  A 96160.03419950 0.00000000  00000-0  00000+0 0    02
2 23862  63.4199 202.4156 0081004 173.4327 186.5673 13.40381315    00

Note that this implies a closing rate (A catching C) of only 6 or 7 seconds
per day, so the two may be very close this evening.

When first spotted, 96 29A showed a pattern that consisted of two flashes
in a 6 second period.  This agrees with what I observed a couple of nights
ago.  It had a base brightness of about 6th magnitude - the two flashes
were only about 1/2 magnitude brighter, but they were very obvious because
they were only about 1/10 second (or less?) in duration.  The two flashes
were separated by 2 seconds and 4 seconds to give a period of 6 seconds.

After about 2 minutes, (3:49UT), it bacame obvious that the flashes were
getting brighter.  As we watched in amazement, the two primary flashes
gradually increased in brightness to about first magnitude.  Each of
the pair of flashes became a "strobe light" of 5 or 6 flashes with
a duration of a little less than 1 second.  This occurred about 3:50UT
about 60 to 65 degrees altitude in the south.

This reminded me very much of the similar behavior of USA 32 and USA 81.
(They also flash at second magnitude very rapidly in a similar part of my sky).

The bright flashes lasted for only about 15 to 20 seconds.  Then they
became fainter and the object returned to its former behavior - two
not-very-bright flashes every 6 seconds on a base brightness of about
magnitude 4.5 (as it neared our zenith).

It is inconvenient to use my Dobsonian to track an object through the
zenith, so we took a two minute break to turn the telescope to the
next predicted position about 52 degrees up in the north.  When re-acquired,
(3:53UT) the object seemed to be doing just the same as before.  But
again I noticed that the flashes seemed to be getting brighter.

As we again watched in amazement, the entire show was repeated at an
altitude of about 30 degrees in the north (3:55:35 to 3:55:50UT).
Since the range to the object was 1200 miles instead of 750 miles,
the flashes were about one magnitude fainter.

I can only push my stopwatch button at a rate of once every 0.2 seconds.
This was a little longer than the separation between the flashes.  So
perhaps the separation was about 0.15 seconds.

I find it interesting that the difference between the two places where the
bright flashes were seen is about 90 degrees.

Speculation time:  If the fundamental rotation rate is 6 seconds and the
rapid flash rate is 1/6 second, then the number of reflecting surfaces
is 36.  As Spock would say, that seems illogical.  But a fundamental
rotation rate of 1 or 2 seconds also seems illogical.

So is this a cylindrical-shaped collection of 36 solar cell panels?
Just like USA 32 and USA 81?

What direction is this rotating cylinder pointing to give specular
flashes both 60 degrees up in my south and also 30 degrees up in my

My co-observer was Ed Cannon.  Observing site: lat 30.315, long 97.866.

Mike McCants