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The Jet Fighter Laser Cannon
fahrbot-bot sends in a Register piece about DARPA issuing the penultimate contract for what is intended to be a jet-mounted laser cannon. The Reg outdoes itself in a BOTEC involving downsizing to shark scale. "The US military will shortly issue a brace of contracts for 'refrigerator sized' laser blaster cannons. One of the deals will see a full-power ground prototype built which will be the final stage prior to America's first raygun-equipped jet fighter. ... If it scales down far enough, this would seem to put handheld HELL-guns within an order of magnitude of the striking power offered by conventional small-arms. A 9mm pistol bullet has about 750 joules muzzle energy: a 5kg portable HELL-ray weapon would put out this much energy in a blast less than a second long. ... A dolphin can carry a human being weighing up to 100kg along for a ride. A thoroughbred shark in good training can surely match this. Thus, we seem to be looking at practicable head-[laser] output in the 20-kilowatt range."
Ok, I see the obligatory "sharks" tag, but what about the "pewpewpew" tag?
Why not compare it to a real handgun caliber? ;)
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
When I read the summary I wondered if they'd be putting one of those on flying robot drones and then I realized that yes, it's 2009 and we live in the fucking future.
In Capitalist America, bank robs you!
I've never heard an analysis of effects on humans. Bullets are good a disrupting tissue, often causing death. A laser might deliver a cauterized burn, or blindness if in the right spot.
Time to get into the mirror business! It's a lot easier to deflect protons than bullets, I'll tell you that.
We've been down this way back during the star wars days and trying to shoot down missiles. Any sort of energy that is released in the term of a second or so is useless against anything but stationary targets where you can assume you will hit the same point for that entire second. Bullets on the other hand expend their energy in a range of ten thousandths of a second. Until lasers or other beam weapons can deliver enough energy in a short enough amount of time similar to a bullet or supersonic missile, they simply will not make good weapons. Just make your missiles spin and any energy hitting them will be over a very large area. Similarly, the energy given for a 9mm hitting a human target that is moving around will be affected less than the firer of a 9mm who will probably absorb that energy over a shorter time and less area due to recoil.
Val Kilmer seen running around MIT hollering with joy.
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If the recoil has the energy of the projected laser but in the opposite direction, the way a bullet gun's recoil does, how is it not enough to notice? The lasers in this article, including the hypothesized portable version, pack quite a wallop.
The recoil has the momentum of the projected laser. Photons, like atoms, have mass-energy which, along with velocity determines momentum. But a lot of energy gives very little mass. So photons have a lot of velocity (C) and hardly any mass, so they have hardly any momentum for a lot of energy.
The atoms in normal rocket exhaust have less velocity but heaps more mass-energy, most of which is just dead weight.
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Which is exactly the sense in which it is used here, as is indicated by the language from TFA quoted in TFS: "the final stage prior to America's first raygun-equipped jet fighter."
So, in the series in which the last (or "ultimate") stage is the contract for a laser-armed jet fighter, the contract for the ground-based prototype is the second to last (or "penultimate") stage.
So, great job of knowing what "penultimate" means, but next time work on reading and understanding the post in which it is used before accusing someone of using it wrong.
Then I take it GNU renders you apoplectic.
Protoplasm. Quiet Protoplasm. I like quiet protoplasm.
All you'd need is a large spinning mirror and you could vaporize a human target from space. Better go make sure someone didn't steal Kents tracking system.
Plus sharks with FRICKIN LAZER BEAMS attached to their heads?
I like the first movie better.
It could be worse. It could stand for the HELL Energetic Liquid Laser.
Also, I'm wondering when the military brainchidren are going to develop the GREATSATAN weapon. Surely this too will help improve our image among people who already think we're controlled by the devil.
"Our two-party system is like a bowl of shit looking at itself in a mirror." - Lewis Black
One of the deals will see a full-power ground prototype built which will be the final stage prior to America's first raygun-equipped jet fighter.
This prototype is second to last(penultimate) contract in this project. The last one (or ultimate) will be for the actual jet. The use is valid.
Give me Classic Slashdot or give me death!
The recoil doesn't have the same energy, but it will have the same momentum.
No, the "ultimate" contract "for what is intended to be a jet-mounted laser cannon" would be the contract for a jet-mounted laser cannon. The contract described here as "penultimate" is for "a full-power ground prototype" intended as to "be the final stage prior to America's first raygun-equipped jet fighter" and which is, therfore, correctly described by TFS as being "the penultimate contract for what is itended to be a jet-mounted laser cannon".
There is lots of misguided pedantry here ragging on TFS for using "penultimate" correctly.
Not only Godwinned but also... Satan? Surely there's a law for that too...
Even though this read mostly like a paranoid rant, it contains just enough grains of truth to be uncomfortable. It IS corporate welfare for Boeing and Raytheon, America DOES fund its own enemies, and the deaths of American soldiers DO enrich military contractors.
The only reason the last paragraph remains a paranoid rant is because I'm worth more to Goldman Sachs as a LIVE victim, rather than a dead one. My taxes justify their bailout.
It begs the question of why people use big sounding words and phrases they obviously don't understand. It literally makes my head explode.
Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
I would like an elegant weapon from an more civilized age.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Yes and no. The amount of energy isn't a terrible base line of comparison if you are doing "apples to apples". There are really 3 factors involved; the energy, how rapidly and efficiently the energy is transferred to the target and over how much area. Sunlight is a pretty good way of illustrating this. In full sunlight you can assume that 1 square foot (30cm x 30cm) receives about 100 watts of energy. Since 1 Joule is 1 watt per second that means that in about 7.5 seconds an area roughly the size of your chest would receive about as much energy as a 9mm bullet.
Obviously this has practically no effect on you. However take a magnifying glass a bit over 1 foot across (32 cm) and focus all of the energy into a spot a little under 1/3 of an inch (9 mm) across and all of a sudden you're causing some serious skin trauma. Likewise if the sun were suddenly 7.5 times brighter you would start to peel and blister in a hurry. Combine all the light of 7.5 seconds into a circle 1/3 of an inch across and apply it all in 1/100th of a second and you'll inflict some real damage.
Unfortunately the laser in their example delivers all its energy about 100 times slower than that. There's also a question of how big the target spot is and of course the fact that just the color of the target can cause a substantial amount of the energy to be reflected (substantial in this case being perhaps a few hundred Joules). So while the total amount of energy isn't a terrible way to compare them that does assume that the beam is focused relatively tightly (probably a safe assumption) and delivers the energy as a sudden single shot (which it clearly doesn't). As it is the comparison is less "apples to apples" and more "apples to orangutans".
Irregardless, I could care less about your head explosions.
Michelangelo: I've got it! I've got it! We'll call it "The Last But One Supper"!
Pope: What?
Michelangelo: Well there must have been one, if there was a last supper there must have been a one before that, so this, is the "Penultimate Supper"! The Bible doesn't say how many people were there now, does it?
Pope: No, but...
Michelangelo: Well there you are, then!
Pope: Look! The last supper is a significant event in the life of our Lord, the penultimate supper was not! Even if they had a conjurer and a mariachi band. Now, a last supper I commissioned from you, and a last supper I want! With twelve disciples and one Christ!
Michelangelo: One?!
The enemies of Democracy are
A dolphin with a laser taped to its head, nailed to an airplane?!!
THIS IS MADNESS!
There has to be some way to put Frickin into an acronym for the shark laser. That way it truly would be sharks with F.R.I.C.K.I.N. lasers on their heads. I guess you could lose the C if needed.