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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?

dirac_10 - 10:20pm Mar 28, 2001 EST (#1648 of 1653)

eurocore - 08:29pm Mar 28, 2001 EST (#1647 of 1647)

Good for you! At least someone on this forum is willing to discuss the subject on a scientific basis.

Use of a laser seems unlikely to me. You'd have to heat part of the structure to a sufficient degree to melt the metal or scramble the electronics within.

We just sold a system to Israel that will do just that. Shoot down a jet or non-ICBM rocket at 10 km. It takes about 10 seconds to do the job.

As the object is fast moving through a cooling airstream,

Which in no way has the ability to cool it down. Look at the very fast jets. They cook red hot. The cool air has no effect.

with (potentially deliberate) variations in acceleration preventing accuracy beyond more than a 20-30cm, (due to microsecond relay time between observation and beam aim correction),

I don't know how you got that. It is true that at intercontinental distances the distance the missle will move in the time it takes light to make the round trip is on the order of 20 cm. But the trajectory is ballistic. We have known since Kepler how to predict where the missle will be next. And the motion is not at right angles, so it would be much less than 20 cm. And it is not technically possible at this time to make a change in velocity that would make any difference. The dern thing is running 20,000 miles/hr. It would take a heck of a rocket engine to make much difference in the time it takes light to make the trip.

and atmospheric absorption taking over 95% of the beams energy

How'd you get that? For all the electromagnetic spectrum? Regardless of modulation or effect on the atmosphere of such energy density?

(over several hundred km via satellite reflection),

After it reflects, there won't be anything like 95%, no air.

it seems you'd have to have at least twenty times as much power as is required to melt a 20cm metal radius disc,

No problem with the 20 times. That one's a piece o cake. We are talking about trivial total amounts of energy.

assuming it were possible to correct for missile acceleration changes at relativistic speeds.

Relativistic speeds? 20,000 miles/hr. ain't even close.

(ie: no lag between observations and correction to transmitted beam - instantaneous electronics!)

Direct on, the ICBM won't move a centimeter in the time it takes light to make the trip. And ballistic stuff is a sitting duck.

The heat capacity of steel is relatively low, but just a thin layer of material on the outside of a potential future ICBM (carbon composite), would make the energy required to destroy the missile quite extravangent.

That's a wild guess. We are assuming our scientists are better than the North Korean ones. Lots of ways of defeating the mirror coating issue.

(Several times more than CERN, for example, uses). If the missile split into smaller warheads, with faster sideways accelerations, the beam radius generated would have increase and the power correspondingly.

Like I said, the dern thing is traveling 20,000 miles/hr. Material objects don't accelerate much in the time it takes light to make the round trip. It would take a brand new kind of acceleration device.

I'd be very interested if an economically feasible laser plan could be created to prevent relatively large numbers of (slightly altered) ICBMs arriving at there targets. I'd be surprised (currently), if one missile was shot down given the above analysis!

Are you innocent of the fact that we sold such a thing to Israel a few months ago? That would explain some things.

This critter, built with chump change, will shoot down a katusha rocket at 10 km. now. Right now. 100 km. is a piece of cake.

And this is what we know about. Entertain the idea that we do not tell the world the details of our secret weapons. Entert

dirac_10 - 10:21pm Mar 28, 2001 EST (#1649 of 1653)

continued...

And this is what we know about. Entertain the idea that we do not tell the world the details of our secret weapons. Entertain the notion that we would tend to keep such things secret. In fact, one thing is certain. We can do more than we are telling.

And we have told the world we can shoot down a jet or rocket with lasers right now. Heck, we are selling it to foreign governments.

lunarchick - 02:20am Mar 29, 2001 EST (#1650 of 1653)
lunarchick@www.com

...... who could turn it around and shoot YOU out of the sky ... leaving a vacuum ... in the emotional and complex minds of those (if any) who deem themselves to be close to you ....

[ following the scientific (?) thiking above:
It's interesting to reflect on the Middle East at the moment where Isreal may have every weapon known to man ... the reality seems to be that Isreal is virtually telling the Palestinian Family in the Hebron Street to stay zipped in their sardine tins and not venture out. Were these arabs to actually habituate such a tin, the next move would be to target the laser beams above on the people in the tins and zap them to death ... Scientific LOGIC is such a joy to comprehend. ]

I'm not religious, but, wasn't there a guy from these parts two thousand years ago whose logic regarding the way forward was to 'forgive' and 'love' ... the 'emotions' are very much a part of any solution that is workable and lasting.

lunarchick - 02:29am Mar 29, 2001 EST (#1651 of 1653)
lunarchick@www.com

A further point re scientific toys of death from simplistic to complex. A point to raise is 'how do those people who are sent to 'kill' 'manage' their own minds for the rest of their lives. How do the Children sent to 'kill' manage their heads through the next eighty years ? The 'emotions' are intertwind in both simple and complex missile defence.

Noting that the current systems are 'unstable' and should have come down a decade ago ... how will 'scientists' think and feel if these silo's blow. What will it be like digging for truffles, looking for deep spring water ... and how short a time would the living last ?

dirac_10 - 02:37am Mar 29, 2001 EST (#1652 of 1653)

lunarchick - 02:29am Mar 29, 2001 EST (#1651 of 1651) lunarchick@www.com

A further point re scientific toys of death from simplistic to complex. ... Noting that the current systems are 'unstable' and should have come down a decade ago ... how will 'scientists' think and feel if these silo's blow.

They should hang their heads in shame regardless. Science is filthy business. Seeped in evil and dripping with blood.

I'm just talking about putting off the time when we will probably be destroyed by it.

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