Topic: OT- Laser and Particle Physics Buffs. What's the upper limit on Laser size?

[Dizzy]

I read where the US military is about to field small fighter size lasers able to destroy enemy aircraft in the blink of an eye: http://www.globalsecurity.org/org/news/2002/021020-laser1.htm

But does size matter? Lets go to the other end of the spectrum... How big can you make one? Granted, the above laser is chemical, as is the one Boeing is mounting on their 747's to shoot down ICBM's called The Airborne Laser: http://www.military.com/soldiertech/0,14632,Soldiertech_ABL,,00.html  but to go really LARGE you'd probably need to go with an energy based device like the laser at the National Ignition Facility: http://www.llnl.gov/nif/project/index.html Animation: http://www.llnl.gov/nif/project/anim_beamline_lg.html

But that, I think, is an energy based laser. So how big (powerful in terms of terawatts and length of time the beam can operate) and how far can they shoot? Is energy consumption an issue? If you built a nuclear power plant and sat it next to a laser built larger than something say, the Giant Megellan Telescope: http://www.gmto.org/  would it be possible to use it to shoot down an ICBM and or multiple rentry warheads if tracking them and keeping them in the crosshairs isnt an issue?

And my last question would be what happens if you take a powerful laser and bounce it off a mirror in outerspace? Will a powerful laser beam even bounce off a mirror? Or will it vaporize the mirror? I can imagine, if it can be bounced and the beam remain powerful enough, a laser beam can be shot from one side of the planet and vaporize a target on the other side of the globe in under a second...

So who knows lasers?

[Nemesis]

Project Excalibur

Nuclear pumped X-Ray laser system.

[Dizzy]

Interesting. That's pretty far out there. Seems there are far more wilder concepts and ideas than mine, which I'll admit has probably been thought of before. Being able to vaporize an enemy target on the other side of the globe within seconds having only to fire a laser bounced off a mirror would seem unimaginably precious... so much so I'm wondering why there's not much on it. Maybe it already exists?

[762_XC]

Mirrors are not 100% reflective. So it would get blasted.

Are you planning on taking over the world or something?

[KBF-Crim]

Mirrors are not 100% reflective. So it would get blasted.

Ah...but a series of focusing lenses wouldnt be....

Are you planning on taking over the world or something?

Hrmf....who isnt these days?

[Dizzy]

Mirrors are not 100% reflective. So it would get blasted.

Ah...but a series of focusing lenses wouldnt be....

Ah, you're right. The NIF's laser uses a multipass mirror relay and doesnt focus the 192 bemas until they are ready to be focused on the target. So instead of the satellite being a mirror, it'd be the focusing lens. Problem solved.

Are you planning on taking over the world or something?

Hrmf....who isnt these days?

MUHAHAHAHAHAHAHAHA! Not unless I get ONE MILLION DOLLARS!

[Nemesis]

Interesting. That's pretty far out there. Seems there are far more wilder concepts and ideas than mine, which I'll admit has probably been thought of before.

Robert L. Forward (formerly of JPL now deceased) proposed making a large array of solar pumped lasers orbiting Mercury and use them along with interplanetary fresnel lenses a 100 km or more across to drive lightsail vessels on interstellar trips.  He had done all the math and proved that it could work.

[ShadowLord]

Diz

If you read up on the new class of Carrier the US is starting to produce you will (CVX?)..
From one show I saw the power plant will be able to produce up somewhere between 3-4 times the power of the current class.
Now granted some of the power will go to new ECM/ECCM systems but I think its understood or expected that the excess power will be used for new weapons systems -- Direct fire energy weapons.

If ya think about these systems are now under development and the new class of carrier will have the power to fire them.

For better or worse the Navy does indeed seem to think ahead as they expect the new class of carrier to last into the next century.

ShadowLord

PS here is a link on the new class of carrier --

http://www.globalsecurity.org/military/systems/ship/cvx.htm

[Dizzy]

I thought the extra power was just for the catapults. I believe they are moving toward electromagnetic than steam powered. But then again, why need aircraft if the carrier can just use a DF energy weapon and blast everything away b4 it even gets close, heh.

[Alphageek]

When I see jet fighters and warships using lasers to zap the bad guys I'll know I've finally arrived in the future.

[ShadowLord]

Diz -- re weapons systems here is a quick cut and paste for ya

There's also been a recognition that electromagnetic rail guns are not ready for deployment with a ship in FY '07. They are still in the state of being developed so that they are not as test articles but as deployable systems. And so the notion that the Navy would back-fit into this first hole or into its next iteration those capabilities as they come on line is very much a part of current thinking, and it has to do with the interior space that is freed up and volume in a ship that otherwise wouldn't have been available.

And from a different article

The next generation carriers and electric warships will be able to generate up to 104MVA (mega volt amps) of power. That is equivalent to a small electric utility power generation facility, or the energy required for approximately 80,000 average US households (907 kWh/month), per DOE statistics.

This power is required for new systems such as the Electromagnetic Aircraft Launch System (EMALS), Electromagnetic Aircraft Recovery System (EARS), electromagnetic (EM) weapons, pulsed energy and laser weapons. All of these systems have at least one thing in common. They all require high energy electric pulses. How these pulses are generated and distributed is a new and novel problem that must be solved. In addition, conventional power electronic systems and design practices result in systems that are 10X too large and heavy for application on the next generation carrier.


Duck

[Nemesis]

But then again, why need aircraft if the carrier can just use a DF energy weapon and blast everything away b4 it even gets close, heh.

Air craft can scout and attack over the horizon and beyond obstacles.  If the enemy ship is on the other side of an island the laser can't hit it but the fighter can.  If an allied ship is between the weapon and the target the target is safe from the DF weapon not from the fighter.

[Dizzy]

That's why I was asking about the space refocusing lens and mirrors.

[CaptJosh]

It is illogical to move away from the steam catabult system. It does what is needed reliably, with an extremely low failure rate, and with much better energy efficiency than an electromagnetic system. Leave it to the navy...

[Nemesis]

It is illogical to move away from the steam catapult system. It does what is needed reliably, with an extremely low failure rate, and with much better energy efficiency than an electromagnetic system. Leave it to the navy...

If your going catapults a Heinlein magnetic catapult could be set up to throw (multiton) rocks to any target on Earth and out at least to the Moon.  Lunar attacking ones would need steering jets for fine targeting.

[Dizzy]

It is illogical to move away from the steam catabult system. It does what is needed reliably, with an extremely low failure rate, and with much better energy efficiency than an electromagnetic system. Leave it to the navy...

I heard that electromag catapults can fire faster than steam putting more planes into the air in shorter time. Then need to be able to do that if china attacks taiwan. Bet ur booties thats where the 1st electromag catapult carrier will be deployed.