calbiterol

NeonBlack - nope. If that were the case, the paint "bullets" would be destroyed as soon as they were fired, because the thin layer holding the paint is not anywhere near strong enough to withstand explosions, which is how all conventional firearms work. The closest thing to explosives launching paintballs from any paintball gun is the new Tippmann C3 (PEP), which detonates small amounts of propane. I know for a fact that at least some American law enforcement and/or military trains with paintball guns (given, most are designed specifically for law enforcement, although most are also available to civillians). Dealing with absolutes is never a safe bet, and I will not say that all military and law enforcement agencies train with them, but at least some do.

 

I suppose there is a remote possibility that what you said is correct, but that would require the engineering of a special paint "bullet" that could both withstand the incredible force of firing and that would make effective use of rifling (rifling barrels with normal paintballs is actually counterproductive, the sloshing of the liquid paint inside makes the ball exremely inaccurate when given any spin other than a backspin).

 

Cheers!

The answer is, absolutely yes. There are commercially available stirling-cycle engines that are powered from the heat of your hand. Stirling engines work on heat differences. It would be quite possible (in theory) to create a (couple) miniature stirling-cycle engines, throw them in the flashlight, power a generator off of the engines, and then run some high-output LED's from the generator.

 

I must add that the best route would be to put rechargeable batteries in the flashlight, and instead of powering the light off of the self-contained power source, recharge the batteries with the power source. That way, you have constant power independent of the power supply, but the batteries won't need to be replaced unless they lose charge (which happens with ALL batteries eventually, even rechargeable ones).

 

Make sense? If not, feel free to ask questions.

I think it's also illegal to have a paintball gun that looks like a real gun.

 

Nope. They do it all the time. Paintball guns are actually used by law enforcement and various militaries as a means of simulating real-life, live-ammo situations, and the guns used by them are available commercially as well.

I meant environmental/scientific issues - I was aware of that treaty, I assumed when you said orbit that you meant exclusively orbit, and not space in general. My mistake. So, to rephrase my question, are you aware of any non-political reasons why nukes couldn't be detonated in orbit?

Another slightly more... unrealistic option is something called the nuclear pulse engine. Well' date=' it's not so much an engine as a crude way of travelling via nuclear fission explosions.

 

Basically you fit a great big lead plate to the back of your spaceship. The idea is to chuck nukes out the back of the spaceship and detonate them in fairly close proximity to the spaceship. The force of the explosion contacts the ablative lead and you get a fair bit of acceleration.

 

Clearly there are some problems with this - making sure your entire crew doesn't die from radiation poisoning, for a start - but it's a good idea [i']in theory[/i]

 

Actually, there's been significant work on this, and it's completely practical. Quite literally the ONLY thing stopping us from building one of these right now (aside from the money/motivation to build one) is the outcry of environmentalists. In reality, there would be no environmentally adverse effects - there are far more dangerous particles already in space (including radioactive ones) that are already being filtered out by the atmosphere and magnetic field.

 

The technology has been proven as well. Both experimental results and mathematical models have been produced. It's not really unrealistic in any way, IMHO. Many of the experiments were conducted to prove that something can survive the power of a nuclear explosion and be propelled by it. The results are quite compelling. In short, they launched various constructs to "some distance away" (project orion). The wikipedia article on nuclear propultion is here. It's quite comprehensive. Check out the other articles it links to as well.

 

Ryan, out of curiosity, why can't nuclear devices be detonated in orbit? Extremely low orbit is understandable (fallout would kill people), but from an orbit as removed as the moon's?

Wouldn't increasing the power of the magnet increase the power output of the coil? In other words, are you using something like a NIB magnet, or something like a common refrigerator-door magnet?

depends on how you do it. One of the ways, I would imagine it would just bypass placing the screen up and boot the computer. The other, it probably wouldn't load - you'd have to go to setup or the boot menu, or boot from an .iso.

Excuse me if this sounds mean, but hence the phrase "artificial intelligence." Any and all intelligent beings have an inherent capability to learn. As such, it should be a given that any true AI construct would also be able to learn - thereby surpassing the intelligence of its human creator(s).

ah, I see what you mean. but the one you liked isn't working, so why don't you just use the other method?

 

Ahh, oh contraire. The one I found by something like trial and error didn't work, and the second one (from the website) which DOES work, is the one I like better anyway. So, long story short, simple misunderstanding, and my bad on the bad choice of words.

Yeah, it is. There's a couple ways, you can either use the task manager to kill explorer.exe, then use the rec. hacker to save a new version, and start a new instance of explorer.exe... or you can follow the directions on the link above to change the actual shell file (exe) loaded. I like the second option myself.

 

Anyways, those are the only two ways I know of, but there are probably a bunch more out there.

The link explaining how to change the shell file worked like a charm (knock on wood). We'll see if it's still working in a few days. I'm keeping my fingers crossed.

GAh! I changed my start text, and when I booted it up later, "Dachs" had disappeared and reverted to the old file, leaving a boring old "Start" . . .

 

And now I can't get it to work again. Any ideas on why this is doing this? It's really, really bugging me. Thanks

Calbiterol, I see your point but I don't see why the feat would be impossible, if you approach it not from the standpoint of an all-orbital space station but a single space station tethered to a single elevator. The elevator doesn't have to be physically tethered to the Earth - why can't it be tethered by that part of its own mass which is within the geostationary orbit, i.e. within the area where the gravity outweighs the centripetal acceleration?

That's not what I'm trying to say. I'm trying two things. The first is that if you put something like this - something that has the capability to spin itself and spans around the entire orbit - in geostationary orbit, then you're going to have to spin it in order to produce gravity at one G. Not too terribly much faster than it is already travelling, mind you, but fast enough to cause extreme strain on the materials of the ring. And then, by spinning it, you're defeating the point of putting it in geostationary orbit anyway, because you'll no longer be continually over the same point on the ground. In theory, this wouldn't matter if you had something with an enormously large tensile strength, because you could just slow down a ring placed in a higher orbit (and therefore able to produce 1g with a lower speed). The force of gravity would just succeed in centering the ring because the fact that the ring has a larger diameter than the earth would prevent the ring from coming crashing down to the ground - assuming the material it was made out of is strong enough to stand such an immense force. However, to the best of my knowledge, this is currently impossible, even with further development in carbon nanotubes.

 

One last hair to split - gravity isn't overpowering the centripetal acceleration, it's balancing it, or equal and opposite.

 

The "anchor" would still be in geostationary orbit. From the standpoint of material tensile strength, the process (in essence, nothing more than the doubling or tripling or so of the cable length and the increase of the mass of the lower part of it) doesn't sound that much more difficult than keeping the huge fricking cable upright in the first place.

You're right, a space elevator would not necessarilly need to be tethered to the ground, but simply hanging it from your ring would require an incredibly large tensile strength out of the materials, something that doesn't currently exist. Keeping the cable itself upright is just a (relatively ) simple task of counterweighting the other end of the cable - let gravity provide centripetal acceleration, while the inertia of the counterweight provides the reactionary push (aka "centrifugal force" ), which will hold up the weight of the cable, and anything pulling itself up the cable. In order to remain at one point on earth, the system would have to have its center of mass at exactly geostationary orbit (hence the counterweight). It's doable, but a bit annoying to implement in the construction phase. That counterweight, by the by, is the anchor I was referring to, not the center at geostationary orbit. Alternatively, by putting its center of mass anywhere BUT geostationary orbit, while technically possible, would result in a cable that spins around the world. Trying to catch the "train" (cable) while it's moving, as I'm sure you would agree, is not the best way of doing things.

 

 

Long story short, this IS possible, maybe even with modern-day technology and materials - although we're quite a bit short on quantity of the materials for an entire orbital ring. The way you'd do it is by counterweighting the ring itself, towards the earth. By locating the ring's center of mass in geostationary orbit, while placing the "walking surface" of the station in a higher orbit (but still attached to the other part), the outside will have a large enough radius to produce one g at the velocity of geostationary orbit, and not require a tensile strength that is immeasurably high. Setting up the system like this, you could have as many elevators as you wanted, as long as the center of gravity (IIRC this is interchangable with center of mass) of the ring remains unchanged. Hopefully that last bit made sense. If it didn't, let me know, and I'll make a drawing for you.

That was my point. If it were required to anchor the ring to the surface, even if it was anchored down miles under the surface, even if materials strong enough to compose such an anchor existed, they would still have such strain on them that they would rip themselves out from the surface, ripping out a good chunk of land - we're probably talking cubic kilometers - in the process.

First, not to nitpick, but there is no such thing as centrifugal force. Second, in order to create centripetal acceleration without constantly firing a rocket, it would be necessary to tether the elevator to the earth. This is not going to be possible for a very, very, very, very long time, if at all. Space elevators themselves are viable as of right now, but the thing is, they ARE NOT reliant on their tether to the Earth. The "anchor" so to speak is in space. And for that matter, if you keep the center of balance at geostationary orbit (which is a vital necessity), then the entire thing will spin at the same rate. Effectively, everything will be in the same equilibrium that exists at the geostationary point in orbit. The reactionary push to the centripetal acceleration of the elevator's center of mass will cancel out gravity. The only difference between orbit and the ground (in terms of gravity) is that the speed of the object is such that the centripetal accelleration is supplied completely by gravity, with no excess or shortage, resulting in a near-perfect state of equilibrium. It is the exact same thing as being in an airplane that is accelerating downwards at exactly [math]9.8 m/s^2[/math]. The people inside will feel weightless, when in reality, they are not - it just depends on your reference point.

 

That last bit might have been kind of vague. Long story short, IIRC, it is impossible to create artificial gravity like you are trying to do.

Who are you referring to, dharvin? And no matter what, exactly what don't you understand?

This idea has actually been posed before. In certain specialized applications (like transportation between bases on the moon, where temperatures are usually low enough for a superconducting state to be reached in some materials without any refrigeration), this is great, and by all means effective and energy-efficient as well as extremely fast. The largest problem (other than economics) that you will run into in space is not, as Mezarashi suggested, the stability problem, but rather the recoil of the system. As Newton said, every action has an opposite but equal reaction. In other words, for every force you exert from the track on the train, the train pushes equally backwards on the track. When you encorporate mass into this, the acceleration of the track could be negligible, or it could be immense. It all depends on the relative masses of the train and the track. If the track were massive (nearly covering an entire orbit of the moon) then it would just spin, meaning that the acceleration of the next ship could be used to stop the rotation of the ring-accelerator, but that is a much longer story. Instead, I wish to provide some background information for you, and a place that you can start to develop your idea from.

The main obstacle for commercializing this is the amount of material needed for magnetic levitation; it's not economical to say the least.

I agree with you 100%. The bane of many exceptionally well-thought, technologically impressive innovations is often the cost of bringing the idea into physical fruition.

 

The second obstacle is stability. Have you ever been able to have one magnet levitate over another just right? Imagine a train on such tracks. One little shake and it slips off just like that. You will need to devise a very complicated control feedback scheme with low response time and minimal overshoot, since overshooting can cause it to slip off the other direction. Although I am confident in our current control technology, the amount of material needed doesn't explain itself.

Here I have to disagree. First, a little background information. Earnshaw's theorem states that it is impossible to levitate something magnetically, but it is VITAL to note that there are many exceptions to this theorem, which is based on a number of assumptions that may or may not be true. Here is a page discussing magnetic levitation, Earnshaw's theorem, and its applications in producing stable magnetic levitation. Note that this does not mean magnetic levitation is completely impossible, because it IS, in fact, possible, it is just impossible under certain circumstances. The example of trying to get one magnet to levitate perfectly above another is a perfect example of Earnshaw's theorem. The magnet will always flip over, attaching itself to the other magnet in the process (probably at blindingly fast speed).

 

Second, these control systems do not need to be complex or dynamic. Manipulation of the arrangements of magnets in the track can produce this effect. Alternatively, a Halbach array can be used to levitate the train, and conventional magnets can be used on either side of the train for stability purposes. Furthermore, the train could simply be placed above a superconducting track (or vice versa), which would be levitated by the Meissner effect, and all the needed stability control could be provided by altering the shape of the superfonducting track (I actually find the German version of this to be more informative, but I can hardly read the German, and I understand that the accepted language here is not German but English). Again, this last example would be ideal in a situation where it could be naturally at a temperature below the superconductor's critical temperature and shielded from sources of heat - like placing it in a tunnel on the moon. Placing it underground would also effectively combat the biological issues that harmful radiation poses.

 

Sorry about the length. I hope it's helpful!

First off, 1/4 a mile in 12 seconds is not that fast. That's 75 mph or 120 kph. Very few off-the-line cars cannot achieve that speed.

 

I agree completely with swansont, YT, and Sayo. And JC Macswell, I have to admit, I'm curious if you're serious or just joking, for the sake of argument.

The needed temperature would max out at about 1400 celcius, about where steel becomes white-hot (needed for welding, if neccessary). Normal operation would be around 1100 celcius.

I actually just read that you can do it with any kind of iron oxide, depending on the ratio of materials. Here it was done with magnetite ("black rust").

Magnesium ribbon or powder is a much better starter, IMHO. Not all alluminum foil is covered in plastic, but that is aside from the point. No, it will not work. The wrong iron oxide (there are a lot more than just rust) will also not work, but this is due to chemical reasons.

That could have some military applications. Modify thermite grenades into molten iron grenades. That would be a "crowd-control" device for sure. Especially since there's no way to stop it.

No worries.

 

I rather enjoy a brief foray into the realm of fiction - it's a nice break from reality sometimes. One of the most interesting science-fiction related aspects of this is the infinite number of possibilities that an extraterrestrial lifeform could take. Something beyond our wildest imaginations would be, to put it simply, breathtakingly amazing.

I apologize if I have offended. There's nothing funny about finding out if there's truth in it, indeed, I do the same all the time and encourage it. Many foundations of modern science are based on the science fiction of the past.

 

The thing that made me laugh was what I must now relate as an extremely unlikely coincidence. There is currently a rather scientifically unfounded (read: pure fiction, with pseudoscience mixed in, probably deemed science fiction) TV show on Friday nights here in the US that includes in its impressively implausible resume the ability of an alien species (possibly a 4- or 5-dimensional one at that) to modify the human genome to a triple helix. The timing was such that I believed this to be where you got the idea; apparently, this is not the case. Had I looked at your location, I could have easily discovered this. The reference to spiral EM interference patters was the alien species's calling card: burned into almost all electronic devices (and arranged in some randomly chosen blood splatters on the floor) was a spiral-shaped interference pattern. So in reality, for you, there is absolutely no connection between the two.

 

Again, sorry, I didn't do the thorough background checking that I should have.

Very good analogy, jdurg.