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It's plausible, but cryogenic fuels are currently only used on takeoff. This is because there's no way to keep your fuel cold; that plume of vapour you see from
by david-given 11y ago
It's plausible, but cryogenic fuels are currently only used on takeoff. This is because there's no way to keep your fuel cold; that plume of vapour you see from the top of rockets on the launch pad? That's fuel being vented because as the temperature slowly rises and the fuel boils. Once you reach orbit you typically switch to a different fuel, which will keep. Deep-space vehicles tend to use hydrazine. Voyager 1 still has hydrazine in its tanks which is 38 years old and it still works fine.
If you're capable of keeping cryogenic fuels cold in, say, the rings of Jupiter where such a shield would be useful, then you've probably got power to burn and don't need to resort to that sort of hack.
- Gravityloss 11y agoHydrogen as well as methane and propane etc were looked at for Constellation's lunar module Altair some years ago. You save a lot of weight since it's much more efficient than hydrazine. At least for the lunar descent you could use hydrogen, that's the most mass anyway and you don't need to worry about heat management at the surface anymore. https://en.wikipedia.org/wiki/Constellation_program#Altair https://en.wikipedia.org/wiki/Constellation_program#Altair Lockheed Martin has been working on lots of technologies for long term flights with Centaur stages. You could have onboard refrigerators etc.. It's not so strange nowadays as it was in the sixties.