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

reuters.com

21–30 of 138 posts

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

#21
post #19

Earlier quoted context omitted.

> 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?

It adds one more element to overcome when we decide we would like to live there.

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

#22

Earlier quoted context omitted.

> 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.

Fun fact: right across from the Hanford Site is a massive Conagra plantation. Source: visited Hanford Site, looked up the company associated with the plantation across the road.

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

#23

If each core really is the size of a paper towel roll, then this seems like a solid step toward me eventually owning a nuclear-powered car.

You will never be allowed to own one because you cannot be trusted to dispose of it correctly.

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

#24
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?

Thats what is bothering you? Did you hear about fukushima? Where are the water to cool it and make steam for the turbine to turn? How much water is needed for a reactor to run safly? What other matterial are they going to heat to turn turbine to produce energy? What is the amount of lost metirial expected over time? And what happen when no cooler matirial is available? Boom?

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

#25
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…

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.

Plutonium isn't toxic, not any more than any other heavy metal.

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

#26

Earlier quoted context omitted.

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.

Plutonium isn't toxic, not any more than any other heavy metal.

It is radiotoxic

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

#27
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.

I haven't heard that before.

原子力(atomic, using atoms)+発電所(power plant) is the common term

eg 福島(Fukushima)第一(No. 1)原子力(nuclear)発電所(power plant)

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

#28
post #20

Earlier quoted context omitted.

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

And as that page also explains, has restarted some of them, and the long-term policy calls nuclear power "the country's most important power source".

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

#29
post #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 t…

> the reactor can just be jettisoned before re-entering Earth‘s gravity well

I think if there’s one thing to be learned from previous missions, it’s that nothing will „just work“. If the ejection mechanism is damaged, or the spacecraft is hit by some object and rendered useless shortly before ejection, then the radioactive payload will make it to Earth. I think a roundtrip would be dangerous, and the core should be left at Mars.

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