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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

#11

Post by baron816 »

gh02t wrote: post #6
baron816 wrote: 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 t…

Ah, ok. Thanks for the explanation.

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

#12

Post by QuarterReptile »

njarboe wrote: post #4
baron816 wrote: 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 r…

In Japan they just call them 'thermal plants' or 'thermal generators' or something like that. Still, in Japan you have people who follow around US aircraft carriers and submarines to sample their wake for any signs of radioactive discharge.

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

#13

Post by pishpash »

gh02t wrote: post #6
baron816 wrote: 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 t…

> 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.

Polluting the new homeland from the start, eh?

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

#14

Post by Jesus_Jones »

pishpash wrote: post #13
gh02t wrote: post #6

Earlier quoted context omitted.

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 t…

> 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. Polluting the new homeland from the start, eh?

Just bury it out back, we'll clean it up later just like we did in Hanford. No problemo https://en.wikipedia.org/wiki/Hanford_Site.

More seriously, we can afford to have a small amount of nuclear waste there, but we need to plan for it better than we have previously. First, document where it is and what it contains. Second, I don't know.

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

#16

Post by King-Aaron »

pishpash wrote: post #13
gh02t wrote: post #6

Earlier quoted context omitted.

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 t…

> 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. Polluting the new homeland from the start, eh?

That's so when the Martian Congressional Republic eventually decides to declare war on Earth, they'll be weakened from the get-go. It's called playing the long game...

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

#17

Post by stevedonovan »

njarboe wrote: post #4
baron816 wrote: 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 r…

Consider the thermal Plutonium power sources that have been sent on outer Solar System missions. One of those crashing is a much more serious problem than a new U-235 reactor, since Plutonium is very toxic.

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

#18

Post by acidburnNSA »

vadimberman wrote: post #15

I'm curious, where does one get the nuclear fuel on Mars? Does it have to be flown all the way from the Earth?

Definitely. You can probably mine uranium on Mars but that would require a bunch of infrastructure and other power sources. These babys are way down-rated so they can run on a single loading of fuel for decades, like nuclear submarines. Good old E=MC^2.

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

#19

Post by ekianjo »

pishpash wrote: post #13
gh02t wrote: post #6

Earlier quoted context omitted.

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 t…

> 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. Polluting the new homeland from the start, eh?

How does pollution work exactly in an environment that's already hostile to life as we know it?

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

#20

Post by ekianjo »

QuarterReptile wrote: post #12
njarboe wrote: post #4

Earlier quoted context omitted.

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 r…

In Japan they just call them 'thermal plants' or 'thermal generators' or something like that. Still, in Japan you have people who follow around US aircraft carriers and submarines to sample their wake for any signs of radioactive discharge.

> In Japan they just call them 'thermal plants'

Japan has completely shut down all operations of Nuclear Plants since 2011. https://en.wikipedia.org/wiki/Nuclear_power_in_Japan

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