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Rail Guns Closer to Reality
emtboy9 writes "Yahoo News is reporting that scientists at Sandia National Labs have created a magnetic pulse gun (rail gun) that can accelerate small aluminum plates at 34 kilometers per second, faster than the Earth travels through space.
The accelerated plates strike a target after traveling only five millimeters, or less than a quarter-inch. The impact generates a shock wave -- in some cases, reaching 15 million times atmospheric pressure -- that passes through the target material turning matter into various states almost instantly (solids into liquids, liquids into gas, and even gas into plasma)."
I think the knife has a longer range than this thing.
They should use some of the technology for cold fusion to accelerate small metal plates into things... That would be hella fun!
-Bill
Start a happiness pandemic
Sounds like we have our Quake 4 in real life before it is released...
Faster, measured against what frame of reference? A marker on the equator versus the center of mass? As seen from the moon? Sol? Alpha Proxima? Vega? The center of Andromeda's galactic core?
[
Plates don't liquify people. People liquify people.
Well, you could maybe launch non-mil payloads into space, or perhaps use the technology in terrestrial transportation... Or make a really bitchin' chicken gun.
"Who are in control, they are not in control of anything - they don't even control themselves!" - Glen Beck
LAQ (Live Action Quake)?
People will pass up steak once a week, for crap every day.
Second paragraph:
Housed at Sandia National Laboratories, the Z machine attracted a lot of attention eight years ago when its energy output more than quadrupled - raising hopes that the reactions in the Z could provide a new source of clean, abundant power. To help further progress towards this end, the machine is getting a $61.7 million upgrade, officials announced recently.
This is a non-military use. They are using it to simulate conditions deep within giant planets. Also this isn't really a rail gun. For one it doesn't use rails, and the whole aim of this experiment is unrelated to rail guns.
what sig?
"a magnetic pulse gun (rail gun) that can accelerate small aluminum plates at 34 kilometers per second"
/. were pedantic nerds with nothing better to do hang out, not CNN.
We were taught this at the age of 14 - what were you doing?
Acceleration is measured in distance per second per second. 34 km/s is a velocity. So did you mean it accelerates it to 34 km/s? Or did you actually mean it accelerates at 34 km/s/s? This is
If you can't get out of the way of the guy carrying a gun bigger than my house, I think it's probably best if your slow-ass organs die with you.
Call it a "rail launcher" and fire satellite payloads into orbit. Of course you'll have to slow down the velocity or the payload will ionize in the atmosphere upon launch. Rail launchers are more practical in a vacuum, as there is no atmosphere to interfere with hypervolocity launches. Perfect for chunking mined ore from the Moon to Earth?
I'll bet this railgun on fires a few millimeters because they have problems with longer magnetic "barrels" exploding from the shockwave produced by an object moving "at the speed the Earth moves through space".
"As for the future, your task is not to foresee it, but to enable it." - Antoine de Saint-Exupery
I am a hippie. Voted against Bush and everything. But it ain't the science that does the killing.
Just because it's called a "railgun" doesn't mean it has military uses. The power supplies and support equipment necessary to power the Z-machine take up several rooms. It's far easier to kill with existing weapons design that it is to reduce the requirements for imparting vast amounts of energy to low mass objects. The chance to study high energy transformations in other-than-nuclear reactions open several potential basic science appliations. The article clearly cites some potential applications that aren't military.
Call me crazy, but I'd rather make a friend than kill an enemy.
Unfortunately, not every enemy feels the same way.
"Plans are for fools! Oglethorpe, the plutonian (Aqua Teen Hunger Force)
How about this: In Soviet Russia the Railgun ... ummmmm ...
No, I can't really see any easy beneficial (which is, I guess, to say "non-military") applications for this tech, unless you can tell me how this could aid in space exploration (a means of launching spacecraft, maybe?) ... or how it might help in the advancement of processing or data storage technology...
Wait! I've got it:
Railgun confirms: Tank crew is dying.
Ahh, that's more like it. Now I can sleep. :-)
Let's hear it for reading comprehension! Between yahoo news and he submitter, we're somehow left with the impression that this is a rail gun. It's nothing of the kind. It's an implosion machine. As described in the LiveScience.com article linked: "The Z uses a short burst of intense electricity - only a few 10 billionths of a second long - that forces an ionized gas to implode." So we can stop the handwringing over the morality of this "weapon", as to use it as such would require luring the enemy into a chamber the size of a soup can and asking him to hold still while you blast him.
If a job's not worth doing, it's not worth doing right.
This is nothing to do with rail guns. It's just a silly inflamatory headline (or maybe railguns are cool 'cause they're in Quake).
This is all about generating massive shockwaves to examine the properties of matter in extreme conditions (without having to heat it up to enormous temperatures).
Repton.
They say that only an experienced wizard can do the tengu shuffle.
Oh - you said RailGun. I guess my brain just saw the additional three letters.
Housed at Sandia National Laboratories, the Z machine attracted a lot of attention eight years ago when its energy output more than quadrupled - raising hopes that the reactions in the Z could provide a new source of clean, abundant power. To help further progress towards this end, the machine is getting a $61.7 million upgrade, officials announced recently.
.45 ACP.
The fact that several mods decided that you post was insightful makes me very uncomfortable with the quality of mods lately. If you read ANY of the TFAs linked, you would see that in this case the gun in question has nothing to do with "maim and kill." In this case, the "rail gun" (it's not really even a rail gun, but that's a whole different issue,) has more in common with a staple gun than my trusty
I believe this link better describes what the Z Machine has to do with rails guns.
and think of the children for once.
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I work at Sandia, on this very topic. These are just flyer plate experiments, using the Z-machine's Marx Generators to isentropically accelerate small aluminum flyer plates up to high velocities, in order to better understand the behavior of metals at high pressures/densities/temperatures. This has been around for a while now. The only difference is they've recently attained these higher velocities by having the Marx Generators switch at slightly different times, rather than all at once.
Nothing to see here, move along. (and pay no attention to the man behind the curtain)
solids into liquids, liquids into gas, and even gas into plasma
Let me guess - it then turns plasmas into solids.
So the war of the future will be an evere more complex version of Liquid, Gas, Plasma, Solid - far more sophisticated than the three state method of old including Rock and Paper.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
This put's the Flux Capacitor to shame. No where did I park that Delorean?
However -- rail guns are on the cusp of military viability. The University of Texas at Austin's Institute of Advanced Technology got 10 million dollars to develop viable rail guns. Just a month ago Janes reported that a prototype of the military rail gun had been tested, and that it was nearing viability.
That article really made me wish I had a Jane's subscription. Apparently, the limiting factor is the size of the capacitor -- if they can get this down than naval applications within a few years are plausible.Incidentally, a fun game, if you're ever bored, is to imagine what would happen to the human body if one were to hold and fire a rail gun (even a wimpy one that shot at a mere 1,600m/s and not at "near the speed of light"), and the law of conservation of momentum actually worked. Really! Try at parties!
Fond wishes,
Moiche
You may have also seen aluminium egg rings fired off older rail-gun devices. The actual material doesn't have to be magnetic, it moves forward because of its own magnetic field induced by current flowing through it. Aluminim is a GREAT conductor of electricity and so makes a similarly great magnetic field. This field, when interacting with the rail gun's, makes it move, NOT the fact that the material itself has (unenergized) magnetic properties. Pretty simple really.
This is the huge tidbit that I haven't really seen discussed: "That's 50 times faster than a rifle bullet, and three times the velocity needed to escape Earth's gravitational field." A rail gun, of sufficient capacity to catapult raw materials into orbit, would be a gigantic breakthrough for the whole planet.
The article's title is extremely misleading.
This does not bring rail guns any closer to reality, by which I mean it does not bring military rail guns any closer to reality.
The Z-machine is a hanger-sized experimental device akin to a particle accelerator. This was an experiment designed to study extremely high pressures, such as those thought to have been important in Jovian planetary formation.
Saying that this experiment brings rail guns closer to reality is like saying that the Large Hadron Collider (LHC) at CERN brings PPCs closer to reality.
The "small aluminum plates" are not just small... they're TINY. Others have already noted that "rail gun" is a big misstatement; the discs they're talking about here are merely 850 MICRONS thick. Let's get this thing in perspective, shall we? I know that "rail gun" makes many geeks twitch uncontrollably, but come on now, that's just karma whoring.
Oh, and to link to a two-year-old image... with a caption of "have created" that implies it's brand new... PLEASE.
Once again, the question must be asked: where's the moderation system for STORIES?
--Brandon / Split Infinity Music
Well railguns are neat and all, but I'm still not joining the Army until they invent the respawn point.
"Derp de derp."
While it's theoretically possible that a weapon might be derived from this research someday, but for a moment think about what this is really talking about.
It's a machine that can accelerate a tiny disc of metal very quickly, but only for a short distance, and AFAICT, it's all happening down inside of a big machine so about the biggest thing you could kill with it might be a cockroach.
Right now, as far as killing things goes, it's not a weapon -- it's just a $6+ million bug exterminator!
Hmm...bug extermination for only $6 millon or so. Maybe MS should buy a few dozen!
--
The universe is a figment of its own imagination.
The universe is a figment of its own imagination.
"The Constitution guarantees us the right to keep and bear rail guns!!!" Later followed by "Mommy... Johnny liquefied the cat again!"
If you could reason with religious people, there would be no religious people
The Z machine (and it's earlier configuration called PBFA 2) have been on Sandia for a long time.
As said above, it's not a rail gun. It's not really even particularly useful for rail gun research.
What it's for is to put small amounts of matter at tremendous temperatures and pressures.
There are a lot of reasons to want to do this. Some of it is just basic research. i.e. What happens to matter and the laws governing it at these extreme conditions?
Another application is fusion power research. You can compress deuturium and tritium to the point they will fuse in this machine. Though it's not made to generate power, you can learn about the details of the fusion reaction.
That said, the main reason why this machine was built was indeed for military research. But even that is in a grey area. The US hasn't conducted a nuclear test detonation in quite some time. The reason it was able to do this is that computer simulations and other methods got good enough that they were able to be used instead of actually setting off a thermonuclear or nuclear device. Indeed, many of the Department of Energy's most powerful computers were created specifically to do that sort simulation (ASCII White, IIRC, for example).
When running computer simulations, you have to have some way of calibrating the simulation and checking that it's getting the right answer.
In the case of a supercomputer run simulating a car crash, you can validate it by conducting crash tests, and seeing how closely it agrees with them. Wrecking a few of a given car model is acceptable in return for it.
But, when simulating nuclear weapons, you would often run into cases where to validate the code, you'd, at first glance, have to set one off. The conditions in a nuclear blast are so extreme, that it's difficult to put matter into that sort of state. If you're trying to maintain a test moratorium, that kinda undermines the whole idea.
That's a big reason PBFA 2 and the follow on Z machine were made. They let DOE check the computer simulations and do basic research that would otherwise require nuclear testing. One of the biggest areas of interest is what happens when the materials in a bomb age. A lot of those weapons are getting quite old.
They have many other basic research uses, but a big one is making it possible to keep the nuclear test moratorium.
So, it's grey area. On the one hand, it's used for weapon research. On the other, it helps keep the test moratorium. It also has a lot of basic research uses. So, just like a supercomputer, you have to make your own decision about whether it, on the whole is a good or bad thing.
Uh, was I the only one who got the wrong article on the "magnetic pulse gun" link? It should be here.
Accelrates at 34 km/s?? I thought that was a velocity. If .5 (at^2) = .005 m
And at = 34000 m/s
...then that makes the time about 3e-7 s. That would be something like 11.8 billion g's.
Not bad. Even for such a small projectile, that's an impressive impulse.
-ex
So many people here are saying things like this because of the stupid, erroneous "rail gun" description Slashdot gave it.
This is not some projectile launcher. It's a massively expensive device that creates immense magnetic fields in a tiny region for fusion and shock wave experiments, of which one thing that you can do is propel miniscule items over short distances. It doesn't "scale" to rail gun applications, and it's not designed to - it's already a monstrously large device. Besides - when it operates, it produces the greatest source of X-rays on Earth. You want to scale that *up*? Next, the G forces in this thing are just plain ridiculous. Last, Earth's escape velocity is not the only thing you have to achieve - did you forget about Earth's atmosphere?
Far, far, far more realistic is Gerald Bull's monstrous barbados gun, which actually would have been launching things to orbit given a few more months. However, using a crazy-expensive device designed for fusion and shock research with crazy levels of X-ray generation to propel projectiles to space an is a ludicrous idea. Why not just propose converting your average nuclear waste storage pool into a rocket because the radiation it emits is very high ISP?
Sigur RÃs: I didn't know that Heaven had a rock band.
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"Well, it varies from person to person."
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It doesn't accellerate the flyer plate linearly. A Z-pinch machine, which the Z-machine at Sandia is an example of, implodes a thin hollow cylinder of material, a fraction of a mm thick and about 1-2 cm in diameter and roughly 1-2 cm long. The Z-pinch effect causes the cylinder walls to collapse inwards at high speed, striking a target along the axis of the cylinder.
See for example http://plasma-gate.weizmann.ac.il/ZP/
High electrical current flows through the cylinder, which causes a magnetic field whose lines of force are circular around the wire. Basic electrical physics. Also basic physics, you get a force ExB (electrical field cross product with magnetic field). The sign of the force, from the direct electrical field and its induced magnetic field, is inwards towards the center of the cylinder.
So at high enough currents, the cylinder implodes.
There's no external magnetic field necessary. If you add one, then the implosion process is more even and stable, but that isn't necessary at all for the Z-pinch effect to work.
You can even do fairly safe home experiments in Z-pinching. Take a bunch of thin wires and a couple of nonconductive disks. Put the disks on a pole, then string the wires from disk to disk so that they form a cylindrical array. Solder all the ends at the top to one electrial lead and all the ends at the bottom together. Connect up to a power source. Watch the wires move inwards.
Z-pinch is just taking that effect, and putting the equivalent of the whole world's electrical power output through it instead of a small regulated power supply. A bit more force, eh?
Calling the Z-machine a railgun is like calling a F-16 fighter a really cool drag racer. Just because they're both fast and burn hydrocarbons doesn't make them at all the same thing.
Does the second Amendment protect our right to turn matter into plasma?
... if you're running around being chased by someone with one of these, chanting, "I refuse to be railed! I refuse to be railed!" repeatedly at high speed will cause them to lose their nerve and not be able to hit the broad side of a barn.
At least, it worked that way in Quake II at LAN parties.
Though it sometimes caused the person with the gun to drop out of the game, reboot into Linux, and start denial-of-service attacking the guy who was chanting...
Do not look into laser with remaining eye.
I hate to say it, but the only way to get peace is with a knife. Men must continue to die in order to preserve peace.
What about women? I think a fair share of them should die too.
Multiplayer Gaming (defined): Sitting around, discussing single-player games with my friends, at the bar.
For every force there is an equal and opposite reaction. Making something go from 0 to 34 in the distance of a gun must produce one major recoil.
Now I foresee a human-carried model! Shoulder rocket launchers let the rocket go on its own - no recoil but don't stand behind the tube. Well, let's replace the burning rocket fuel with a rail gun. The rail shoots out the back in slow motion and the payload goes out the front much much faster. Right? But we're talking magnetic fields at work so....the rail can be curved!! What does that mean?
North and south. Poles that is - double barrel shotgun. As long as both barrels shoot at once one side balances the other as long as the force should cancel at the back end.
Just in case some entrepreneur wants to build one now, remember Equal and Opposite. The rail has to be flexed. In other words, think sawed off shotgun, and even think crossbow. The rail has to be horizontal for the most part until the ends where the ammo is turned by the electromagnetism to shoot forwards. Almost all the force should occur in the horizontal portion while the forward pointing portion doesn't give any more force than a normal gun.
Kind of scary, espcially if the high speed projectile doesn't want to turn the corner at the end, not to mention the long lever arm will make the rails flap. Automatic fire will have to be timed.
The only problem left? electric power for something like this must be pretty big. Kinetic energy = 1/2 mv^2 so even a small m will require a lot of car batteries. I don't see 007 running around with this weapon protecting ski bunnies while his batteries freeze.
Know your pads. One time pad: good for cryptography. Two timing pad: where to take your mistress.
Call me crazy, but I'd rather make a friend than kill an enemy.
Unfortunately, not every enemy feels the same way.
So lets kill them before they kill us!..
You realize how many conflicts could have been avoided if someone had stopped and realized that the other side is human too? Very few people actually want to kill, and even less people want to be killed. People kill out of fear, and killing people because you dont want them to kill you is the worst abuse of logic around.
Im willing to bet that every enemy really does feel like they would rather make the friend. Don't get me wrong, I dont mind people running out and killing eachother, I just dont buy their justifications.
Now that weve gone completely off topic (as the original article wasnt even about guns), heres a bash.org quote!
I think it should read accelerate to 34km/s, not at
what's your problem? Earth's orbital velocity is ~29.8km/s (thus Earth travels though space at 29.8km/s relative to the sun). those plates are travelling at 34km/s. is 34km/s not faster than 29.8km/s?
That said, that's significantly slower than Earth's `orbital' velocity around the center of the galaxy: 300km/s (yes, 0.1% c) assuming the sun is 100000 ly from the center of the galaxy and it takes 100 millioin years to go complete an orbit.
Bill - aka taniwha
--
Leave others their otherness. -- Aratak
So we can stop the handwringing over the morality of this "weapon", as to use it as such would require luring the enemy into a chamber the size of a soup can and asking him to hold still while you blast him.
HEAR HEAR! I quite agree with the parent. This should be a discussion about the morality of lureing your enemies into soup can sized implosion chambers and asking him to hold still.
(It doesn't sound cricket, if you ask me...)
HA! I just wasted some of your bandwidth with a frivolous sig!
Rail guns are unlkely to be useful for driving implosions. It would be very hard to focus a symmetric implosion with a railgun. However, you could use the same pulsed power to drive an implosion like a plasma gun. Get a thin gold tube, fill it with DT, and whack in a pulse. The pulse goes up the outside of the tube. The gold outside goes directly to plasma, stops conducting, and so the current can move inward. If you can get the shockwave reaction from the expanding plasma to approximately match the speed of the current penetration, then a nice, cylindrically symmetrical implosion should be yours, and the small burst of annoying penetrative radiation and the hair loss that goes with it.
There is another effect - the Z-pinch - that is a bit railgun-ish. This gets a lot of mention in the Sandia webpage. People used to have great hopes for that - it was quite the thing in the seventies, when people could still use phrases like 'everlasting power from seawater' without laughing - but it is hard to get a symmetrical pinch before instabilities run riot.
Don't take my word for it. Maybe, I'm too old, and things have moved forward since I last was in this field. Sandia is a seriously cool place, even if the people who write their webpages are a bit too keen now and then.
From the linked Wikipedia article: Peaceful uses of railguns There is interest in using railguns as mass drivers for space exploration and mining. They would be useful for launching bulk ores into space, particularly from low-gravity bodies such as moons and asteroids; electrically powered from solar panels, they would not require any consumables such as rocket fuels. Rail guns have been proposed for use in delivering projectiles to space, especially from bodies without atmospheres (such as the Moon). Its main competitors are coil guns and ram accelerators. Also, railguns may be used to initiate fusion reactions, by firing pellets of fusible material at each other. The impact would create immense temperatures and pressures, allowing nuclear fusion to occur. However current railguns are not yet sufficient to achieve the energies required.
Heck, I can throw a rock faster than the Earth travels through space - as long as I'm at the equator, the local time is near midnight, and I'm throwing the same direction as the Earth is traveling. And don't go trying to get relativistic on me.
You never really know how close to the edge you can go until you fall off.