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Ok I have a question kinda related about bubbles traveling faster through a medium.

If objects underwater can supercavitate, can objects in the atmosphere also supercavitate and can we have objects orbiting the earth inside the atmosphere?




That's an interesting question. Supercavitating torpedoes take advantage of two effects (a) gas typically is much less viscous than liquid, which reduces drag and (b) if you reduce the pressure enough, liquid turns into gas.

In the atmosphere, you're already in a gas, so there's not an obvious other state of matter that would be advantageous. Furthermore, reducing pressue would certainly reduce drag, but not by orders of magnitude like a phase transition.

But in the spirit of 'yes, and': if you reduced pressure near the skin by A LOT (near vacuum) you might see a dramatically lower drag. Maybe that could be accomplished by ionising the incoming air and then electrostatically repelling it? Who knows. It's fun to speculate though.


In that spirit, pointing lasers in front of a hypersonic aircraft to shift the shockwave in front of the vehicle rather than on it: https://www.thedrive.com/the-war-zone/33859/blasting-the-air....


Interesting, like a laser version of https://en.wikipedia.org/wiki/Drag-reducing_aerospike

without the LSD Wave.




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