Re: Iridium flares, 30 Aug 97

JRBURCA@aol.com
Fri, 26 Sep 1997 03:40:05 -0400 (EDT)

Ed Cannon wrote:
<< Theoretical Iridium flare question:  Since they may flare to -8 and
 apparently always flare opposite the Sun, what are the chances -- if
 any! -- of observing a flare while the Sun is above the horizon 
 (especially if they prove to be reasonably predictable)? >>

I don't think that the Iridium must be opposite the Sun to get a flare.
Unless I was "seeing things", the one I reported on 9/15/97 "Obs.
One Iridium Flare 15-Sept.-97 @ 12:26 UTC" was a morning pass
east of the meridian.  The sun was AZ 104 EL -15 and the Iridium
(one in the Iridium 27-33 group) was approx. AZ 10 EL 20.  Here
is a small quote expressing the unexpected brightness:

"........... I saw for about one or two sec. a very bright flare through
a relatively clear spot between the clouds.  I'm not good at judging
magnitude but it seems to me that it was close to the brightness 
of Venus............."

It seems the sun-satellite-observer angle would be something in the
neighborhood of 90 degrees.  But the satellite and the Sun were both
east of the meridian.  Suggest that interested Iridium observers don't
discount those type of circumstances in looking for bright flares.

Jake Rees
Burbank, Calif.