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U.S. tests nuclear power system to sustain astronauts on Mars

reuters.com

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Re: U.S. tests nuclear power system to sustain astronauts on Mars

#4
post #2

What happens if the launch rocket fails? That’s been the main concern of sending nuclear reactors into space thus far, right? Has this been addressed here?

It is too bad that most people are so afraid of anything nuclear. I hate to say it, but maybe people working on nuclear power need to change the name. Isotopic power would have pretty bland associations.

Uranium 235 is a very low level radioactive metal. Even if the rocket blew up, the isotopic fuel would remain intact (that is, not vaporized into breathable particles). The radioactivity from a Uranium 235 isotopic reactor comes after the reactor has been running for some period of time (from byproducts of the nuclear reaction), not the original fuel itself.

Re: U.S. tests nuclear power system to sustain astronauts on Mars

#6
post #2

What happens if the launch rocket fails? That’s been the main concern of sending nuclear reactors into space thus far, right? Has this been addressed here?

It's not really a concern. U235 is basically radiologically inert, it doesn't become significantly radioactive until after the reactor has been running for a while. The concern with fission reactors in space is for stuff that might return to Earth after it's been in operation long enough to build up other isotopes that are radioactive and subsequently burning up in the atmosphere. For a vehicle that is on a one-way trip to Mars, and where the reactor will be brought online after it's out of Earth's orbit, this isn't a problem.

Edit: even on a round trip it wouldn't be a big deal, the reactor can just be jettisoned before re-entering Earth's gravity well. You just can't have a fission reactor with spent fuel anywhere near Earth orbit. Space reactors in general are pretty interesting, because the design criteria are so different from terrestrial power reactors.

Re: U.S. tests nuclear power system to sustain astronauts on Mars

#7
post #3

I would love to have more details about this reactor. How much is the total mass? What is the expected power output over time? What kind of heat sink is necessary? But in any case this is really cool development.

There is a veritable orgy in nuclear tech for space here:

https://beyondnerva.wordpress.com/

See also

https://github.com/briligg/moonwards/wiki/Nuclear-Reactors--...

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