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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 - 03:24pm Feb 4, 2002 EST (#11233 of 11259)

mazza, perhaps in this particular instance, I misjudged your intention. In fact, you're right -- there is information there to adapt.

When I walked away, after posting, I had a sinking feeling about that. We all get testy, from time to time. You've done it. Pardon, this time.

I'll be working according to the patterns you've referred to.

All the same, on the question

. Is there a reference for the adaptive optics to adapt to, to produce anything close to the resolution needed?

the answer appears to be a clear no.

rshow55 - 03:29pm Feb 4, 2002 EST (#11234 of 11259)

Even if the optics were perfect, and could focus on a true point, or something close to it, from a range of 100 miles -- you'd still have to aim it to a similar accuracy - - otherwise, the beam would sweep and shake across so much area, so fast, that it would do no damage.

There are, as Mazza's reference points out, a chain of things that have to happen together, which have to be accurate enough to make the system work.

rshow55 - 03:30pm Feb 4, 2002 EST (#11235 of 11259)

There are many "miracles" needed here -- together.

gisterme - 03:35pm Feb 4, 2002 EST (#11236 of 11259)

rshow55 2/3/02 4:02pm (WRT adaptive optics)

"..."The question is "adaptive of what, with respect to what?"

Any detail you can supply would be appreciated -- without those details, I'll make estimates, and try to be clear about them..."

Your eyeballs have one organic example of adaptive optics. You can actively change the focal length of their lenses just by looking to different distances. Adaptive optics in telescope terms are mirror controls that offset atmospheric distortion in real time to get "in focus" pictures through a varying atmosphere. They accomlish this by dynamically changing the shape of the mirror. Naturally, if you can change the shape of the mirror, you can also change the focal length. Just try a web search for "adaptive optics". You'll find plenty of details there if you're really interested.

The Hubble space telescope has no need of adaptive optics because it's not looking through atmosphere or trying to focus on nearby objects.

rshow55 - 03:49pm Feb 4, 2002 EST (#11237 of 11259)

The question isn't whether adaptive optics works in general -- of course it does. The question is whether it works in this case.

In MD11229 rshow55 2/4/02 10:28am I asked:

" Is it common ground that there is no reference source, focused on the missile or other target, that is available for the adaptive optics of ABL to work from?

"If there is such a source, is there anything, of an unclassified nature, that can be said about this miraculous source?

Obviously adaptive optics works. And works the way it does, and works as well as it does.

Adaptive optics has to adapt to something. For hitting a target -- something on the target -- where's the reference on the target, and how does the referencing means "see" well enough to serve as a refernce for the adaptive optics. How is it made or adjusted?

There's an expression about "pulling yourself up by your own bootstraps." Nice poetry, but it doesn't work physically. Adaptive optics can't adapt with respect to itself, either.

I asked an essential question. Do you have an answer - - rather than an evasion?

mazza9 - 04:55pm Feb 4, 2002 EST (#11238 of 11259)
Louis Mazza

RShow55: The Adaptive Optics post I referred you to said that the original thoughts on this process were laid down in 1953. Computers and deformable mirrors did not exist. When the original SDI work was performed in the mid 80s we were just transitioning to 386 machines and Super computers were new and unwieldy. But, the mirrors were made, the algorhythms were mathematically derived and the adaptive optics were proven in the astromonical world. You need only look at the improved resolving that is displayed at the AO site.

Today a Playstation, at under $300, has more processing power than an 80s era Cray Supercomputer,(that's why Iraq has been buying them to circumvent our export controls on super computers!) The MEMS mirrors are fuctional. There was a picture of one mirror set with the initials BU for Boston University. The students were documenting where the research was done.

A Laser "radar" is much more precise than the radio frequency version. The FAA system which is still in operation today, when in raw video mode will return a blip of an aircraft which when viewed to scale would display an aircraft that is 1 mile in diameter. This is one reason why aircraft separation is so wide (6 miles for similar aircraft). Lasers bounced off the Apollo laser reflectors measure the distance to the moon in inches!!! At 100 miles the laser could count the rivet holes on the missile body. Once lock on occurs and the missile trajectory is calculated the ABL, using the newest computers, (I've got to believe that the Air Force is not using Apple IIEs), with gigahertz speeds would have little difficultiy keeping the aiming laser focused on the missile. The tracking sensor would lock on the aiming laser reflection. This return signal would be sensed and used to measure the turbulence between the missile body and the ABL station. The feedback loop would send the trubulence correction signals to the deformable mirror, continuously, and when the "SHOT" is fired ...ZAP YOUR DEAD"

LouMazza

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