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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?

Read Debates, a new Web-only feature culled from Readers' Opinions, published every Thursday.

rshow55 - 08:46pm Feb 4, 2002 EST (#11244 of 11259)

We're talking about very far fetched resolutions, when we imagine that the ABL, or other laser weapons, can actually work -- (and especially, that they can work with simple reflective decal countermeasures.)

The NASA people were right that "using a rifle to hit a moving dime two miles away" is hard -- and would be hard even with a perfect rifle, and perfect bullets, and would be hard even shooting in a vacuum.

For ABL, you need resolutions far greater -- and starting without really knowing to good resolution where the target is - - and with little information to help with that - and with little time to find out.

. . . .

Nor can the "adaptive optics" work, either. There is no "high precision" feedback loop to the target, for the adaptive optics to focus with.

Some while ago, when there seemed to be some shock that reflective countermeasures were easy, gisterme commented, and quite rightly, that a mistake and a fraud aren't the same.

But if you get enough of them, piled one on top of the next . . you get to wonder.

lchic - 09:11pm Feb 4, 2002 EST (#11245 of 11259)

... where WishyWoo's laundrette is ....

gisterme - 11:17pm Feb 4, 2002 EST (#11246 of 11259)

rshow55 2/4/02 7:47pm

"...How does this happen? This "feedback loop" is exactly what doesn't exist..."

Wrong again, Robert. A wider angle lower power beam, probably modulated to improve SNR would be used to illuminate the target, probabaly guided by an infrared sensor of some type. The light returning from that modulated beam would be used analyse real-time atmospheric conditions between the target and the laser and also determine range and precise line-of-sight angle. The feeback loop would consist of the known reference signal leaving the targeting laser compared to the return signal reflected from the target. The feedback time latency at a range of 1000 miles would be about 10 mS. Plenty quick enough to respond to atmospheric conditions and get range to the rocket. A rocket travelling at mach 5 only moves about 55 feet in that amount of time, probably not even its own length. The strike from the high-energy laser would take about another 5 mS to get there...of course leading a target travelling at a known speed is no problem. If the range is only 100 miles, then conditions are ten times better of course. And chances are, the rising target could be hit before it ever reaches that kind of speed.

mazza9 - 11:35pm Feb 4, 2002 EST (#11247 of 11259)
Louis Mazza

Rshow55:

There are two choices.

1. It can't work because RShow55 says so.

2. It can work because a great deal of resources and dedicated intelligent individuals are laboring to overcome the technical challenges.

The AO system works. Why do you suppose that earthbound astronomers are planning the next generation telescopes will have better resolving ability due to AO if the theory didn't work? The application of AO is the same in a telescope and an ABL. The Keck Observatory in Haiwaii will have different requirements then the ABL. Aircraft jitters will be absent but volcanic jitters will be present. Know your noise and you can blank it, (learned that from a friend who is a Ham operator!). today there are sophisticated laser gyros that can sense minute movements, (at one wavelength of the frequency that is used in the laser gyro). The jitter can be measured and eliminated. The tracking of the missile is no different than past gun laying techniques. The only difference is the signal source of the tracking laser and the extremely high speed of current generation computers.

RShow55, I can appreciate that you are not a believer. Fine. Today's issue of Aviation Week reported that the Navy ABM test using a Standard Arm anti aircraft missile had made a suucessful test firing on Jan 25th. The launch was made from the USS Lake Erie.

To get back to the forum issue, Will it work and does our national security warrant the expenditure of resources. We need to protect our armed forces, (remember a SCUD did kill 28 service men and woman in Saudi Arabia during the Gulf War) and our nation in general. Yes i know it will work.

When JFK set our sights on the moon, our abilities were just alittle removed from the V-2 era. Within 8 years we were walking on the moon. I happen to believe that whatever man can dream he can fashion. Good Night

LouMazza

lchic - 11:52pm Feb 4, 2002 EST (#11248 of 11259)

Why did JFK set USA sights on the moon .. when there was so much that needed and needs to be done on terra firma .... Yes, why did he keep the pigs at bay then to skywards look and pray?

gisterme - 11:54pm Feb 4, 2002 EST (#11249 of 11259)

Here's a timely link showing some non-military AO capabilities...

http://dsc.discovery.com/news/reu/20020128/saturn.html

gisterme - 12:04am Feb 5, 2002 EST (#11250 of 11259)

"...Yes, why did he keep the pigs at bay then to skywards look and pray?"

Cast not thy pearls before swine lest they trample them under foot then turn again and rend you... --Jesus

Could it be that JFK somehow found out about the half-dozen tactical nukes the Russian commanders had available to use if the US tried to invade Cuba? Those local commanders were authorized to use them at their discression. Now that's scary! I believe it scared the hell out of Krustchev when he realized how little control he had.

I belive JFK realized that real war was not an option...so, knowing he had a superior economic and technologial engine under the hood, decided to step on the gas. Potential is interesting but results are everything aren't they, lchic?

mazza9 - 12:05am Feb 5, 2002 EST (#11251 of 11259)
Louis Mazza

lchic:

JFK was smarter than you!

mazza9 - 12:20am Feb 5, 2002 EST (#11252 of 11259)
Louis Mazza

Gisterme:

I think we saw the same show on the History Channel. However,my 11251 was to the point and used less syllables.

LouMazza

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