Superbird-A, ETS-6, 97 86B, old Hipparcos obs

Mike McCants (
Tue, 10 Mar 1998 06:00:23 -0600 (CST)

I estimated that the maximum of Superbird A occurred about
2:55:30UT Mar 10 as seen from Austin, TX. (30.314, 97.866)
I measured 24.5 cycles in 570.0 seconds to give a period
of 23.265 seconds.

There was also a minor maximum about 3:11UT.  Brightest
flashes were to about magnitude 7.5.  If I use one of these
timings, I get 51 cycles in 1186.0 seconds for a period
of 23.255 seconds.

I observed ETS-6 at 10:47:30UT with 7x50 binoculars
flashing to about magnitude 5 or 6.  I timed 4 cycles with
a period of 20.0 seconds.  I suspect I missed the "main show"
which probably occurred about 10:30 or 10:35.  It was a couple
of degrees north of Iota Librae.  I believe that this is the
object that Jeff Medkeff and the airline pilot saw.  The range
was apporximately 22000 miles.  (I did not generate predictions. :-)

I observed ETS-6 from 2:20 to 2:30UT at a range of only 9000
miles.  I timed 51 cycles in 510.5 seconds, giving a period
of 10.01 seconds.  The maxima were to about magnitude 7.  Some
were easily visible in my 12x80 in spite of a bright moon.
The maxima rose and fell smoothly, with a flash on top.
The secondary maxima occurred 1/2 between the primary maxima
at magnitude 8 or 8.5.  They also rose and fell smoothly
over a time of about one second.

I observed 97 86D (25129, Asiasat 3 Rk, Proton 4 upper stage)
from 3:30 to 3:32UT.  It was tumbling from magnitude 5.0 to
7.5 with a period of about 1.5 seconds.  I measured 88 cycles
in 129.1 seconds to give a period of 1.47 seconds.  The range
was 1200 miles since it had passed through perigee to the
northwest of me a few minutes before.  The Asiasat 3 payload
is also stuck in an eccentric orbit.

Another notable flashing payload:  On the evening of July 20,
1996, Ed Cannon discovered Hipparcos (20169, 89 62B) flashing
near Saturn.  It was flashing to magnitude 7 or 8 at a range
of over 25000 miles.  The period was 8.2 seconds.  I subsequently
measured a period of 2.02 seconds in October, 1996.

Mike McCants
Austin, TX (30.314, 97.866)