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Missile Defense

Technology has always found its greatest consumer in a nation's war and defense efforts. Since the last attempts at a "Star Wars" defense system, has technology changed considerably enough to make the latest Missile Defense initiatives more successful? Can such an application of science be successful? Is a militarized space inevitable, necessary or impossible?

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rshow55 - 06:12pm Feb 8, 2002 EST (#11369 of 11370)

MD11226 rshow55 2/4/02 8:00am offers some discussion of a reference provided by LouMazza, from the Center for Adaptive Optics http://cfao.ucolick.org/ao/index.shtml

This schematic diagram of the process involved in adaptive optics is very good, and I hope people look at it carefully. I hope we can agree that this schematic, and language connected to it, are well grounded references helping to define what adaptive optics is http://cfao.ucolick.org/images/aos_small.gif

( To get a bigger, clearer image of http://cfao.ucolick.org/images/aoscheme.gif . . . go to http://cfao.ucolick.org/ao/index.shtml and click for a larger image. )

Below the diagram, from the same site, is this passage:

"The most basic systems use a point source of light as a reference beacon, whose light is used to probe the shape of the wavefronts. This may be a bright star, or in the case of vision research a laser spot focused on the retina. Light from this reference source is analysed by a wavefront sensor, and then commands are sent to actuators (pistons) which change the surface of a deformable mirror to provide the necessary compensations. For the system to work well, it must respond to wavefront changes while they are still small; for the earth's atmosphere, this means updating the mirror's shape several hundred times a second! (to image a STAR - a point source of exactly predictable position.)

Now, with respect to the ABL system, or any other laser weapon system designed for MD, the target isn't a star, but a moving missile or warhead (or one of many decoys).

MD11214 rshow55 2/3/02 4:02pm asks some questions, with respect to AO for missile defense:

" ...-- what does the adaptive optics adapt to ... in the specific case of ABL?

Adaptive optics, as defined in the reference, approximates the resolution available from a reference -- rather than improving on that reference. If that's the situation, then 1 arc second is a very optimistic estimate of the resolution available from adaptive optics for the ABL system . . an estimate far too optimistic, in my view.

1 arc sec isn't nearly tight enough for ABL to do what it is supposed to do -- burn up missiles in boost phase.

If I've made a mistake here, what would it be?

rshow55 - 06:27pm Feb 8, 2002 EST (#11370 of 11370)

gisterme , the post just above doesn't explicitly respond to your MD11367-11368 gisterme 2/8/02 6:02pm -- but the basic question above still seems to me to be a crucial one -- sufficient to rule out ABL.

I'll be dealing with some other aspects of your MD11367-11368 as well.

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