Re: Unusual UnId or (EGP)
Robert Reeves (rreeves@connecti.com)
Sun, 25 Oct 1998 23:07:55 -0600
-----Original Message-----
From: Jim Nix <nixj@bellsouth.net>
To: SeeSat explosive <SeeSat-L@blackadder.lmsal.com>
Date: Sunday, October 25, 1998 10:54 PM
Subject: Unusual UnId or (EGP)
> Later, I checked passes for the evening and found that this
>"aircraft" matched, near perfectly, EGP 16908, (86061A)'s trajectory.
>The observation abruptly ended at the time EGP passed into shadow
>
> Has anyone else observed this object and noted the unusual flashing?
>
EGP has always been one of my favorite objects. It is in a high enough
orbit that it can make many passes in a single night. In fact, in the
winter
when the earth's shadow is low over the northern hemisphere, EGP can
be seen all night on repeated passes if the orbit is just right for the
season.
The satellite itself in an aproximately two-meter diameter ball with many
flat
mirrors attached to it. It was the payload on a first test flight of a
Japanese
booster about 13 years ago. I don't remember the specifics of its
construction, but I remember it as being a cheap (and possibly expendible
if something went wrong on the booster's maiden flight) geodedic test
satellite.
I think it is a stiff wire mesh ball with dozens of approximately 6-inch
mirrors
attached to it. The slow tumble of EGP makes the mirrors reflect the Sun
toward the observer, creating the random blinking effect.
You would not think that a 6-inch mirror would make such a flash at a 1600
mile altitude, but I have watched EGP in binoculars pass with the full moon
(ouch) in the field of view and never loose sight of the "twinkling".
If any of you have never seen this little "sparkler", it worth your effort
to go
out and see it. It is visually dim, with the instantaneous blinks perhaps
about
5th magnitude (what do you expect from a 6-inch mirror?), but EGP travels
so slowly across the sky that you can easily find it in binoculars by
sweeping
the expected orbital path.