Whopper Iridium flares!

MALEY, PAUL D. (paul.d.maley1@jsc.nasa.gov)
Mon, 25 Aug 1997 07:15:55 -0500

This morning I was set up and ready to observe the newest Iridiums at
culmination (57 degrees elevation, azimuth 275) when I was distracted by
a very bright slow moving object in the southwest predawn. Luckily I had
my low light level video system set up, but by the time I swung it over
to the position the flare had faded out (about 6-8 seconds). Then I saw
another -4 magnitude flaring object in the same area and trained the
video on it, then another new object joined in!, then as those two
faded, another new -4 magnitude flaring object! Four of the 5 Iridiums
were observed to flare to between -3 and -4 for roughly the same length
of time. 

While I have not reviewed the tape, I hope I had enough sense to press
the record button.  The positions of the flare activity of 24907, 24906,
24905 and 24904 (I think 24903 was exempt from the super flare) was in
the area of elevation 49 degrees, azimth 230, phase angle of 39 degrees
as computed by QUICKSAT. Times of predicted passes in that area ranged
from 11:02:16 to 11:03:47 UT. One remarkable thing is that two of the
objects were -3 at the same time as they passed through this tight
little region of the sky.  It was very impressive. As the objects
approached culmination they had dimmed to around +5.5 magnitude which is
more typical of an anti sun reflection.

Tomorrow morning there is another pass in the same region 3 minutes
earlier.
Paul D. Maley
DO5/Cargo Operations
NASA Johnson Space Center
Houston TX 77058 USA
phone: 281-244-0208
fax: 281-244-7622
email:      paul.d.maley1@jsc.nasa.gov
       
latitude 29.5378 north; longitude 95.0868 west; altitude 6 m