Shawn wrote:
Sam Wormley wrote:
JS wrote:
Latest news is that the U.S. will try to shoot down the errant
satellite believed to be in the KH-11 class. The pretext is that the
spy satellite contains "hydrazine propellant" that could be hazardous
to humans, but I wonder? I'm sure the military wouldn't want anyone
getting their hands on any debris falling over land...

http://www.cnn.com/2008/TECH/space/0...ite/index.html





Space Weather News for Feb. 14, 2008
http://spaceweather.com

Malfunctioning spy satellite USA 193 has been in the news lately
because of expectations that it will reenter Earth's atmosphere in
March and turn into a spectacular fireball. Reentry has not yet
begun, but sky watchers are already noticing the satellite as it zips
over Europe and the United States shining as brightly as a first or
second magnitude star. Typical photos are shown on today's edition of
http://spaceweather.com.

In fact, USA 193 may never reenter--at least not in one piece. Today,
the Pentagon announced it will attempt to blast the satellite with a
missile before its orbit decays. This would lessen the chances of
dangerous satellite debris and fuel reaching the ground while
increasing the population of space junk in low-Earth orbit.

I doubt if many of the pieces of the satellite will attain sufficient
energy from the impact (or explosion-will the missile have a warhead?)
to be boosted into a significantly higher orbit. All the resulting
little bits will for the most part have a higher surface area to mass
ratio than the intact USA 193. The orbits of the pieces should decay at
least as fast as the whole thing. Also, if they blast it near perigee
even the boosted pieces will be dipping just as far into the atmosphere
as the satellite was, so they should come down pretty soon as well.
It just doesn't sound like all that bad of an idea to me (especially for
the current crew running the show).

Shawn

Sorry for replying to my own post, but I just realized perigee is likely
to be over some part of the world where they really hate us, so maybe
not such a great idea blasting things over the Middle East, Russia or
China after all. Hrmm.


Shawn