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There is a working technology that uses a pulsed laser beam to propel a specially shaped vehicle. When the laser bounces off the tail of the vehicle it heats the air immediately behind causing a burst that propels it forward.
Could the same thing be done with a series of artificially induce, but naturaly powered, lightning discharges? Imagine a free ride into space.
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Elaborate on the "artificially induced but naturally powered" part. I'm having trouble imagining that.
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Lightning is pretty unpredictable, and its heat energy is dissipated along the length of the bolt, which can zig-zag wildly and only occurs in the troposphere (<30,000 ft). I don't see immediately how you could use that in any way for an orbital vehicle, especially since the laser-powered vehicle you refer to is already feasible and would be much easier to control than lightning. The energy required to get to orbit is actually not that high compared to what we easily produce on the ground, so if you can somehow figure out a way to decouple the energy source from the vehicle, generating the required energy on the ground is pretty trivial. You might as well just plug into the power grid rather than wait for the "perfect" electrical storm to send you on your way.
Of course it would be funny to see launches scrubbed because the weather was too nice.
Banned
A lighting rod is used to trigger a lighting strike and released the electrical potential on the rod. You would have to take off in the right conditions. Conditions where the electrical potential exist naturally.Originally Posted by W.F. Tomba
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Perhaps lightening could be controlled. I recall an experiment when a lighting strike was induced with a charged particle beam or a laser I am not sure.There are other kinds of lightning. Ball lightning perhaps. Perhaps the vehicle could absorb the potential of the lightning a create its own discharge with that potential.How does it strike the ground then? Interestingly this fact sparked the notion of tapping into the earths energy potential for this use aka the shuttles tether experiment.I believe there is an issue with a powerful enough laser. There are potential focusing issues over long distances through an atmosphere. The laser looses power as the amount of atmosphere it has to burn through increases.Perhaps the storm could be artificially created of directed. Relatively subtle energy changes can direct hurricanes. Clouds can be seeded. Some places get frequent intense thunderstorms naturally.
Of course it would be funny to see launches scrubbed because the weather was too nice.
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There's still a lot of unpredictability. I'm working with an experiment involving generating ionized regions in supersonic air flow with DC discharges (sort of like very tiny lightning bolts), and I can tell you that getting spark discharges to behave the way you want is a royal pain-in-the-wind-tunnel.Perhaps lightening could be controlled. I recall an experiment when a lighting strike was induced with a charged particle beam or a laser I am not sure.
Changing the potential of the vehicle will still create a discharge to somewhere either on the ground or in the atmosphere, which means energy is not being deposited where you want it to, namely right behind the vehicle where a reaction mass can propel you forward.There are other kinds of lightning. Ball lightning perhaps. Perhaps the vehicle could absorb the potential of the lightning a create its own discharge with that potential.
The troposphere goes from the ground up to around 30,000 ft. The tether experiment demonstrated a good way to generate electrical power on orbit, but the problem with achieving orbital velocity with a free-flying vehicle is that you need to have a lot of power confined to a very small place. The power generated by the space shuttle main engines is often quoted in units of # of Hoover Dams, and all those Hoover Dams have to fit into relatively tiny thrust chambers. If you can think of a way to direct and confine all the energy in a lightning bolt to a small region just behind the rear of the vehicle in such a way that enough steady and reliable thrust could be generated to get you to 25,000 mph without crushing your passengers (or electrocuting themHow does it strike the ground then? Interestingly this fact sparked the notion of tapping into the earths energy potential for this use aka the shuttles tether experiment.) , then you've got yourself a launch vehicle.
There are some technological hurdles to overcome, but I don't think they're nearly as severe as attempting to harness the power of a lightning storm. You also have the added benefit of launching just about whenever you want.I believe there is an issue with a powerful enough laser. There are potential focusing issues over long distances through an atmosphere. The laser looses power as the amount of atmosphere it has to burn through increases.
Banned
Tazers seem to be able to discharge the arc right where they want it. If the potential can be tapped and drawn off to power the vehicles discharge then you have you controlled discharge. Perhaps some kind of monofilament or trail of ions to draw the charge to the vehicle. It seems to me the tricky part is in attracting the potential to the vehicle not the discharge of that potential.
This launch concept would only require a fraction of what a conventional rocket requires because it does not haul its fuel. There is a cascading effect of not hauling all you fuel. Since this will make launch costs orders of magnitude cheaper multiple smaller ships may be used. The vehicle does not need to be 100 percent efficient in any case. Since it is tapping into a for all practical purposes limitless energy source it does may only need to utilize a small fraction of the energy available.The tether experiment demonstrated a good way to generate electrical power on orbit, but the problem with achieving orbital velocity with a free-flying vehicle is that you need to have a lot of power confined to a very small place. The power generated by the space shuttle main engines is often quoted in units of # of Hoover Dams, and all those Hoover Dams have to fit into relatively tiny thrust chambers. If you can think of a way to direct and confine all the energy in a lightning bolt to a small region just behind the rear of the vehicle in such a way that enough steady and reliable thrust could be generated to get you to 25,000 mph without crushing your passengers (or electrocuting them
You may be right.
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1.21 Gigawatts!!!! (Sorry I just couldn't resist)
In all seriousness, researchers down in Florida have triggered lightning strikes using small rockets trailing copper wire down to the ground. Unfortunately, it sounds like they would still need the right conditions (thunderstorms nearby), and sometimes the bolt still doesn't behave as planned.
The professor who ran the experiment, Vladimir Rakov, has a website with some interesting publications on it, although in his FAQ section he doesn't seem to think too much of using lightning as an energy source.
Banned
Thank you for responding to this post.1.21 Gigawatts!!!! (Sorry I just couldn't resist)
In all seriousness, researchers down in Florida have triggered lightning strikes using small rockets trailing copper wire down to the ground. Unfortunately, it sounds like they would still need the right conditions (thunderstorms nearby), and sometimes the bolt still doesn't behave as planned.
The professor who ran the experiment, Vladimir Rakov, has a website with some interesting publications on it, although in his FAQ section he doesn't seem to think too much of using lightning as an energy source.
Interesting links. I would suggest that this research represents a start.
Order of Kilopi
A taser fires two electrodes that trail wires back to a fully charged capacitor in the "gun". When the electrodes contact flesh, the capacitor discharges through the flesh of the target. This delivers an incapacitating (but hopefully non-lethal) jolt.Tazers seem to be able to discharge the arc right where they want it.
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Thank you for responding to this post.
I do not know the nature of a capacitor. I think it is involved in some sort of short-term electrical storage. Do you know why a capacitor is used in this capacity?
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I seem to remember that lightning is caused by a descending stepped leader of minimal potential from the cloud to the ground, at which point the surface charge is tripped and a return stroke ascends into the sky.
Perhaps some type of vehicle could use this effect directly of by powering some other form of propulsion like a Hall Effect Thruster. Perhaps a more direct thrusting could be created in phenomena like blue sprites and the gamma bursts in thunderstorms if the craft is able to be above the burst, such as a high altitude lighter-than-air ship.
Or you could try launching using the updraft of a thunderstorm. Now you just have to find a convenient tornado when you need it...
Banned
Some posters suggested using magnetic fields to control friction and heat problems of high speed aircraft by controlling the flow of air near the vehicles surface that has been ionized by the friction of the vehicle.
I suggest using this technique for thrust. A plasma arc in front of the craft could create the plasma than could be directed away from the craft to produce thrust.
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A capacitor is essentially a very narrow break in the current. The current stops, of course, but it causes a build-up of negative charges at one end of the break and a positive charge at the other end. This represents a potential that can be used to generate current when you want it. But this potential will eventually disappear.Thank you for responding to this post.
I do not know the nature of a capacitor. I think it is involved in some sort of short-term electrical storage. Do you know why a capacitor is used in this capacity?
The actual physics behind capacitors is far more complex.
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:-? I think the predominate force in tornados in a downdraft... But I've been off on my posting lately...
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