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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?

rshowalter - 09:10am Jul 4, 2001 EST (#6536 of 6540)
Robert Showalter showalte@macc.wisc.edu

In MD6521 rshowalter 7/3/01 7:35pm .... I made a request:

" . . . would you have numbers (perhaps expressed in microradians) for the angular resolution of your radars? DOD folks DO use radar to do much of the aiming of these proposed anti-missile weapons, do they not?

and gisterme, to her credit, did not contest the point. She said this instead - - - -

...." It would take a pretty big antenna to achieve microradian resolution with a radar, wouldn't it Robert? Let's see, with sub-millimeter wavelenghts...maybe if we used the entire state of Arizona...Naa. Bad Idea. Senator McCain would never approve. :-) Maybe a radar interferometer...

" Joking aside, your point is right, radars can't begin to approach that kind of angular resolution. Their best accuracy is for ranging and they must be quite good at tracking since that's what they're used for. A large-antenna radar could probably give position data about as accurate as GPS data for a re-entry vehicle a couple of thousand miles distant. . . .

It is useful to understand how such positioning might be possible, it is complicated, but it isn't greek to me. It uses the pythagorian theorem (the square of the hypotenuse of a right triangel is equal to the sum of the squares of the other two side.) and does a lot of arithmetic -- assuming a good right angle. There are limitations that come from that -- at the level of time and angle mensuration, the level of noise filtration, and the level of brute arithmetic -- that make the guidance of lasar weapons, whether from ground or orbit, far fetched.

The numbers on how far short the radars are on angular resolution are compelling - there's a shortfall, if I remember, of many factors of ten from what would be needed - but I haven't gathered them, and my memory could be wrong. -- I haven't searched the place where the best numbers for the angular resolution of the best radio (radar) sensors will be -- radio astronomy.

rshowalter - 09:12am Jul 4, 2001 EST (#6537 of 6540)
Robert Showalter showalte@macc.wisc.edu

I recommend the very rich information accessed from http://www.fas.org/spp/starwars/program/

MD6523 lunarchick 7/3/01 7:57pm ... cites http://www.fas.org/spp/starwars/program/us_starwars_laser_02.jpg as "one big blur" -- look at how far out in time things are "scheduled" . Many years out, for really basic tests of hardware that has to be shaken out well, for a long time, before anything tactical on lasar weapons can make sense.

Reasonable design jobs, that work in detail on paper, to engineering standards, get done, and into prototype testing and production, much faster than that. Long lead times mean that show-stopping problems are not solved, and people are winging it.

I don't think this administration can possibly be happy with the way they are being fed information by the military industrial complex. Just now, I'm feeling a good deal of sympathy for gisterme . Most of the high officers in the Bush administration, as usual, are not trained scientists or engineers -- they are lawyers and political scientists. And on some of the most essential things possible, they are making decisions on the basis of corrupted information.

And betting the survival of the country and the world on that corrupted information. It is an example where better judgement ought to be expected, I believe.

rshowalter - 09:14am Jul 4, 2001 EST (#6538 of 6540)
Robert Showalter showalte@macc.wisc.edu

All this to respond to a threat that doesn't credibly exist (in the terms described) -- and to the neglect of threats that are real.

lunarchick - 09:29am Jul 4, 2001 EST (#6539 of 6540)
lunarchick@www.com

Expressing optimism about U.S.-Russia relations despite numerous disputes, Russian President Vladimir Putin ... Putin ...

rshowalter - 09:32am Jul 4, 2001 EST (#6540 of 6540)
Robert Showalter showalte@macc.wisc.edu

Good !

I'd like to mention MD6518 rshowalter 7/3/01 6:54pm again.

Both gisterme and I have agreed that "missile defense" -- even as a "potempkin village" never deployed, would be worthwhile if it decentered a previously frozen situation, and led to a workable , big reduction of world risks and military problems.

What do people want? Or is the question too complex? . . . Maybe it just takes work to adequately define, and some balancing.

MD6478 rshowalter 7/3/01 4:09pm .... MD6496 rshowalter 7/3/01 4:53pm

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