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

reuters.com

31–40 of 138 posts

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

#32
post #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 r…

"maybe people working on nuclear power need to change the name"

Renaming things with bad public images is a popular trick.

Windscale > Sellafield

Blackwater > Xe Services > Academi

Philip Morris > Altria

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

#33
post #29
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…

> 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 l…

in that case you could still divert the vehicle itself, assuming it's unmanned. My point is: yes, leaving it on mars is a pretty safe solution, but it's not the only one.

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

#34
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 happened many times that a nuclear device exploded or by other means entered atmosphere. Lunch site explosions also happened. I think the on the ground accidents are less serious because you can contain them and it is less spread out than for example a satellite exploding in the higher atmosphere.

https://listverse.com/2012/01/20/top-10-space-age-radiation-...

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

#35
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.

That already happened. Not something we'd want to happen regularly, but not as dramatic as one (me) would have thought.

https://en.wikipedia.org/wiki/Kosmos_954#Aftermath

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

#36
post #29
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…

> 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 l…

The political fallout will probably be more dangerous than adding another kilowatt-class nuclear reactor to decaying megawatt-class ones on sunken submarines.

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

#37
As far as I understand it they are pumping the equivalent thermal energy as an actual operating core would produce into the reactor casing and assembly using a specially designed electrical insert that uses external power.

This isn't a fission test. It's a mechanical engineering test. Still cool.

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

#38
post #32
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…

"maybe people working on nuclear power need to change the name" Renaming things with bad public images is a popular trick. Windscale > Sellafield Blackwater > Xe Services > Academi Philip Morris > Altria

The Blackwater one always mystified me. It’s like they set out to be villains.

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

#39

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.

This oddly reminds me of the story of Fallout.

https://en.wikipedia.org/wiki/Fallout_(series)#Setting

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

#40
post #29
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…

> 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 l…

things are more and more likely to work now we can simulate things with computers first.
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