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Missile Defense

Russian military leaders have expressed concern about US plans for a national missile defense system. Will defense technology be limited by possibilities for a strategic imbalance? Is this just SDI all over again?

lunarchick - 08:51am Jul 7, 2001 EST (#6729 of 6732)
lunarchick@www.com

http://www.guardian.co.uk/submarine/story/0,7369,517812,00.html

rshowalter - 12:01pm Jul 7, 2001 EST (#6730 of 6732)
Robert Showalter showalte@macc.wisc.edu

gisterme , I'm looking at the references you cited gisterme 7/6/01 6:38pm and so far have no reason to modify what I've said about feasibility. The notion that "if we can see it we can hit it" is all through the program, and is ridiculous. In the first days of the artillery course that Napoleon took, people would have been clear that this wasn't true -- then or now -- for fundamental reasons.

Suppose you have the optics of Space Telescope. And three light sources, each putting out the same number of photons to the Telescope mirror. Each a circle, each of an angular extent less than 5 x 10e-7 radians.

One with an angular extent of 2 x10e-7 radians;

one with an angular extent of 2 x 10e-8 radians;

one with an angular extent of 2 x 10e-10 radians.

The largest has 100 times the area of the middle source, and a million times more area than the smaller source. To Hubble optics, these sources look (almost) exactly the same -- you could tell the largest from the other two - but the other two would be indistinguishable.

To destroy the target, you have to hit its area -- does anyone really believe that, in this example (which is the simplest and easiest) if you can see it, you can hit it?

Nobody who has ever shot a gun at a target, and experienced how hard the bullseye is to hit, compared to the outer circle, can possible believe that. For one thing, it depends on how well you can see. And it also depends on what you have to shoot with, and how closely you can control the shots.

rshowalter - 12:02pm Jul 7, 2001 EST (#6731 of 6732)
Robert Showalter showalte@macc.wisc.edu

I must say that the Air Force, and contractors, can hire good commercial artists when they're trying to make something look good.

But the AF is setting out to build systems where, at MANY stages, angular resolution has to be MUCH better than Space Telescope's resolution, on the basis of signals you can't reasonably get.

I'm taking the time to do some reading. At the level of execution of bits and peices, no doubt there's some nice work scattered through the program. All the same, at a systems level, the phrase I've quoted from Menken

"as devoid of merit as a herringfish is of fur"

seems entirely applicable.

rshowalter - 12:06pm Jul 7, 2001 EST (#6732 of 6732)
Robert Showalter showalte@macc.wisc.edu

If the numbers of needed resolution are "classified" and not discussable, you can put together a good story for lasar based missile defense. If you put numbers in there related to what people can actually do in the open literature, in areas where people have been both well equipped and sophisticated for many years - - then the things I've said, that you can accesss by searching the word "shuck" fairly apply.

This system can't possibly work, and if the people building it don't know that -- they've carried self deception, and communal deception, very far. Jim Jones comes to mind.

We're dealing with something here that is either an enormous fraud, or a "tragedy of errors" (I can't bring myself to call it a "comedy of errors.)

I wonder how many people in the program actually believe that "if we can see it we can hit it?"

I wonder how many of them would be willing to say so in public? In terms of the limitations that are really there.

I'm taking time to read the stuff several times.

Some very fancy implicit claims are being made for the controls, which move a mirror very closely related to the mirrors on telescopes. The whole thing is hopeless, and a gross waste of resources and human lives that is also endangering the United States and other nations -- pushing us to unsafe and false decisions.

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