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Hovercraft in space

Heat rocks and move vehicles with them
  (+2)
(+2)
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A hovercraft is an ideal vehicle for moving across rocky, uncertain terrain, and there are a number of places they could be used which happen to be quite far away. Unfortunately many of those places don't possess a convenient atmosphere with which to fill an air curtain.

Rocket propulsion is obviously too inefficient. Wheels can jam, break, or sink. Tracks have the same shortcomings as wheels. But given a good skirt it should take relatively little gas to lift a hovercraft into a vacuum. All that's needed is a free source of gas.

This hovercraft would travel over rock, liquid, or ice by heating it. Inside the skirt would be a nuclear furnace capable of vaporizing a small amount of whatever is under the craft. The craft would then float along on the vapor. Much less heat would be needed, of course, in the case of liquid or ice.

Internal deposition could be mitigated by flexing the skirt to break off any solids, or by heating it as well.

Voice, Dec 16 2019

Orbital Hovrecraft Orbital_20Hovercraft
almost relevant [FlyingToaster, Dec 16 2019]

[link]






       If the surface is, for example, lunar regolith, you're going to end up with a cushion of plasma under your vehicle. Not that that's a bad thing, and we commend your ingenuity. But the interior of the plenum chamber is going to have to be lined with highly refractory material.   

       Since the vehicle is in vacuo, a fusion reactor vented into the volume would provide a flow of hot gas, and would be much lighter than a fission reactor and the relevant energy conversion subsystems.   

       The vehicle would have the distinct advantage of leaving a nice smooth remelted track, like a slug trail, behind it, suitable for wheeled vehicles; in fact, it would be an excellent way of roadbuilding.   

       In the absence of surface contact, and as you eschew reaction engines, how is the vehicle to be propelled ?   

       We will do a few experiments and get back to you, but [+] for the general principle.
8th of 7, Dec 16 2019
  

       I suggest venting a little of the gas for propulsion. If you can keep it hot enough you won't have any contact with the ground, so you'll just keep going until you vent in the other direction. Bonus: if your moon is sufficiently smooth you'll be able to reach orbital velocity, at least in the sideways direction.
Voice, Dec 16 2019
  

       Don't get run over.
pertinax, Dec 17 2019
  
      
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