Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!ucsd!pacbell.com!att!cbnews!cbnews!military
From: henry@zoo.toronto.edu (Henry Spencer)
Newsgroups: sci.military
Subject: Re: Anti-Balistic Missiles Now
Message-ID: <1990Dec15.014052.16357@cbnews.att.com>
Date: 15 Dec 90 01:40:52 GMT
References: <1990Dec7.011307.474@cbnews.att.com> <1990Dec8.221641.27118@cbnews.att.com> <1990Dec12.030935.9815@cbnews.att.com> <1990Dec13.032732.18386@cbnews.att.com>
Sender: military@cbnews.att.com (William B. Thacker)
Organization: U of Toronto Zoology
Lines: 20
Approved: military@att.att.com



From: henry@zoo.toronto.edu (Henry Spencer)
>From: xrtnt@amarna.gsfc.nasa.gov (Nigel Tzeng)
>... I also don't know of any "ballistic" type of missile with
>any sort of active terminal guidance...

The Pershing 2 had terminal guidance, actually, using a scene-matching
system.  And the guidance problems of attacking a warship are considerably
easier than those of land attack, since the sea background is much simpler.

There is some difficulty in doing this for really long-range missiles,
however, because reentry velocities are high, which leads to dense plasma
sheaths around the warhead and severe materials problems for windows.
(Note:  warheads and spacecraft are very different, because spacecraft
work hard at decelerating at very high altitude where G-forces are
manageable, while warheads try not to decelerate at all.)
-- 
"The average pointer, statistically,    |Henry Spencer at U of Toronto Zoology
points somewhere in X." -Hugh Redelmeier| henry@zoo.toronto.edu   utzoo!henry