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NASA Revives Plan to Put Nuclear Reactors on Mars

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Re: NASA Revives Plan to Put Nuclear Reactors on Mars

#71

Post by valuearb »

cortexio wrote: post #23
8draco8 wrote: post #17

Earlier quoted context omitted.

Genuine question: If it's possible to use mini nuclear reactors in satellites then why they just can't land that thing somehow on Mars (like they did with Curiosity) and use it on planet surface to power lab?

Mini reactors are useless on Mars. The power they generate is waaay to low compared to the money that is needed to bring them there. Also putting nuclear reactors on sattelites almost never happens and is VERY DANGEROUS. It's what the Soviet Union did in the 70s-90s. The last sattelite launched with a nuclear reactor was in 1988. You have to be pretty insane to launch large amounts of nuclear material from earth in a…

U-238 is pretty stable.

Re: NASA Revives Plan to Put Nuclear Reactors on Mars

#72

Post by jerrylives »

simias wrote: post #63
tehwalrus wrote: post #54

Earlier quoted context omitted.

I would say, given the state of politics and the general attitude to the climate and natural resources, our first priority should be colonising another planet. Putting some scientists on Mars for a few years is step 1 in that very important insurance scheme!

I don't know if I agree. Creating a self-sustainable colony on Mars will take a very long time and even if we manage to do it can we really afford to "lose" the earth? Mars is an inhospitable hell for humans and practical terraforming technology is still in the realm of science fiction. Maybe if we manage to destroy earth completely out of selfishness and hate we don't really deserve to spread the virus throughout th…

>If we can't sustain our development in a civilized manner on a lush and hospitable planet I don't think we'll fare much better on Dune.

Arrakis at least had an oxygen and nitrogen rich atmosphere.

Re: NASA Revives Plan to Put Nuclear Reactors on Mars

#73

Post by nrb »

simias wrote: post #63
tehwalrus wrote: post #54

Earlier quoted context omitted.

I would say, given the state of politics and the general attitude to the climate and natural resources, our first priority should be colonising another planet. Putting some scientists on Mars for a few years is step 1 in that very important insurance scheme!

I don't know if I agree. Creating a self-sustainable colony on Mars will take a very long time and even if we manage to do it can we really afford to "lose" the earth? Mars is an inhospitable hell for humans and practical terraforming technology is still in the realm of science fiction. Maybe if we manage to destroy earth completely out of selfishness and hate we don't really deserve to spread the virus throughout th…

I agree about self-created problems, but what about annihilation through any other "natural" mass extinction event? I'd argue that to be a good motivating factor.

Re: NASA Revives Plan to Put Nuclear Reactors on Mars

#74

Post by avar »

dredmorbius wrote: post #55
avar wrote: post #46

Earlier quoted context omitted.

My original point was that dredmorbius's comment that Pu-238 is in low supply wasn't referencing some law of nature, but a political decision that could be changed. I said they were a "bad idea for general power generation", so I'm not suggesting that they be used to power a Mars colony, but rather that the reasons not to do so don't include Pu-238 being in low supply. We also have a low supply of rockets & other inf…

There are laws of nature involved. But also of men, nations, and war. Pu-238 isn't found in nature, but has to be synthesized. The precursor material, U-238 is the most abundant form of Uranium, which is convenient. It's also produce via neptunium-237. The real complication is that the nuclear synthesis processes are also those used for nuclear weapons production, which makes for some serious complications.

Those complications only apply to nations that don't have a permanent seat on the UN security council. There are no treaty obligations preventing the US or Russia from making Pu-238.

Re: NASA Revives Plan to Put Nuclear Reactors on Mars

#75

Post by logfromblammo »

foota wrote: post #3

Are there fissionable materials on Mars?

It doesn't matter, as the only infrastructure available for refining fissile isotopes is on Earth. Even if you found appropriate ores directly adjacent to the reactor site, they would still have to be shipped back to Earth to turn them into reactor fuel.

You need fully mature steel, aluminum, and electronics industries on Mars before you can think about UF6 centrifuges. The rocket equation just murders any idea anyone might have about shipping any kind of factory-in-a-box to any other rock in the Solar system--except one that takes in the local regolith and produces a copy of itself, or a similar factory-in-a-box with a different combination of inputs and outputs.

You're trying to jump right from putting the ore in at one end, and getting reactor fuel out at the other, but you apparently need at least a North Korea-sized economy inside the black box to do that, and Mars currently has an economy smaller than Sealand. There are no humans on Mars, and the robots currently there don't mine or farm anything in excess of their own immediate needs.

Re: NASA Revives Plan to Put Nuclear Reactors on Mars

#76

Post by jwilk »

dredmorbius wrote: post #19
legulere wrote: post #14

How will they convert heat into electricity? On earth you have plenty of water as a good medium for the heat and a thick atmosphere that serves as the heatsink. On mars you have neither.

Sterling-cycle generator, utilising heat pipes, based on this study (PDF): http://permalink.lanl.gov/object/tr?what=info:lanl-repo/lare... Tracked via Wikipedia, which has a brief article: https://en.m.wikipedia.org/wiki/Kilopower

Non-mobile link:

https://en.wikipedia.org/wiki/Kilopower

Re: NASA Revives Plan to Put Nuclear Reactors on Mars

#77

Post by simias »

nrb wrote: post #73
simias wrote: post #63

Earlier quoted context omitted.

I don't know if I agree. Creating a self-sustainable colony on Mars will take a very long time and even if we manage to do it can we really afford to "lose" the earth? Mars is an inhospitable hell for humans and practical terraforming technology is still in the realm of science fiction. Maybe if we manage to destroy earth completely out of selfishness and hate we don't really deserve to spread the virus throughout th…

I agree about self-created problems, but what about annihilation through any other "natural" mass extinction event? I'd argue that to be a good motivating factor.

That's an interesting proposition, but how realistic is it really?

If we're talking about something like a huge asteroid colliding with the earth and/or a huge volcanic episode that would trigger a mass instinction, wouldn't the pale blue dot still be more hospitable than Mars? We have access to technology the dinosaurs didn't have, our chances of survival would probably be much better overall.

Even in case of man-made devastation, such as mass pollution or a nuclear winter I think it's safe to assume that Earth would still be more habitable than Mars.

How about something even more destructive? Maybe something like a gamma ray burst? Well then Mars is probably not far away to put it out of harm's way, although maybe they would be more likely to be unaffected by it if it hit the other side of the planet due to its very thin atmosphere? I'm not sure.

Re: NASA Revives Plan to Put Nuclear Reactors on Mars

#78

Post by menzoic »

tehwalrus wrote: post #54
simias wrote: post #10

Earlier quoted context omitted.

I agree with your sentiment but let's face it, sending humans to Mars is as much PR as it is scientific research (maybe even more). Look how we ended up on the moon in the first place. If NASA wants to get the funding it has to make it as marketable as possible. If there's a big push back from the general population it will be hard to convince the politicians to invest billions in an unpopular project with no short-t…

I would say, given the state of politics and the general attitude to the climate and natural resources, our first priority should be colonising another planet. Putting some scientists on Mars for a few years is step 1 in that very important insurance scheme!

If we could terraform a planet as barren as Mars, wouldn't fixing earth be significantly easier?

Re: NASA Revives Plan to Put Nuclear Reactors on Mars

#80

Post by mirimir »

nkrisc wrote: post #47
krasin wrote: post #13

Earlier quoted context omitted.

On a related note, I very much like the fact that "The Martian" movie uses RTG as a life saving device and the best car climate control ever. It helps with the public perception that it's not that dangerous.

Generally I agree with you, but I don't know if it's wise to promote the unintended use of a device by a fictional character as a last hope in a dire survival situation as the bar for what's "safe". Regardless of whether it's actually safe, showing me it's safe enough to sit near in a situation where one would probably die anyway isn't exactly comforting.

Well, NORAD guards used to keep warm by standing in front of the dishes. I vaguely recall that some also figured out that doing so temporarily reduced their sperm count ;)
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