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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

#71

Post by SideburnsOfDoom »

ourmandave wrote: post #69

Unanswered in article: How long does the power unit lasts until you have to replace the paper-towel-roll-sized U-235 core? Where are they going to put the old ones? What's the plug interface? Can I charge my iPhone? What about my electric razor? Are they going to test burying one in red sand for 15+ years and see if it can be dug up to phone home in an emergency?

And in 15 years, do you need to import a new core from Earth or what - have a uranium mining and refining operation up and running by then?

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

#72

Post by nurettin »

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?

Not sure if applicable here; but where I come from they say "the fearful won't have kids"

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

#74

Post by fyfy18 »

ifdefdebug wrote: post #70

I find it frustrating NASA talking about putting people on Mars but if you look at reality, it can't even put astronauts in the orbit anymore. What about solving that problem first, and when it's done, then we can dream about Mars... Or are we going to outsource such mundane tasks like manned orbital space flight to the Russians and Chinese forever, while we are proudly preparing the colonization of Mars? /s

What’s wrong with collaborating and using the collective knowledge of the human race to achieve this? It’s really no different than using private contractors to do the same thing.

NASA can’t do everything themselves, so why not let Russia launch the rockets while the US and other countries focus on other parts of the mission?

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

#75

Post by zach43 »

ifdefdebug wrote: post #70

I find it frustrating NASA talking about putting people on Mars but if you look at reality, it can't even put astronauts in the orbit anymore. What about solving that problem first, and when it's done, then we can dream about Mars... Or are we going to outsource such mundane tasks like manned orbital space flight to the Russians and Chinese forever, while we are proudly preparing the colonization of Mars? /s

> it can’t even put astronauts in orbit anymore

But this isn’t really a NASA problem, this is a US government funding problem right? I can’t imagine how anyone can put people in space without the budget for it

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

#76

Post by SigmundA »

superkuh wrote: post #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.

From my understanding the fission part is "easy", the hard part is taking the heat and converting to electricity efficiently and reliably.

The Mars Curiosity rover among other probes use a thermocouple based generators to create electricity from the fission heat[1]. Extremely robust , no moving parts, but extremely inefficient just a few percent converted to electricity the rest to heat. The heat is very useful on mars though due to the low temps, kinda like your combustion engine in your car, the waste heat can be used to provide useful heating, but still most needs to be rejected and it only puts out about 100 watts of electricity.

This new one looks to be striling engine based which means its going to have much better efficiency since it is a more standard heat engine with moving parts, prob 20-40%. Hence the higher output. However that comes with much more complexity and things to go wrong over long term use.

I still wonder if there is much more efficiency to be had from thermocouple's if the research effort was put into it, it would be similar to solar cell improvements over the last few decades. You just don't hear about thermocouple R&D and if it where improved to say a typical solar cell efficiency of 18-20% it would open all sorts of doors.

1. https://en.wikipedia.org/wiki/Radioisotope_thermoelectric_ge...

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

#77

Post by schiffern »

jacobush wrote: post #55
acidburnNSA wrote: post #18

Earlier quoted context omitted.

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.

I don't think there is any uranium to be had there. For such heavy elements to get deposited in ore near the surface takes special circumstances, such as those of Earth.

What pertinent "special circumstances" do you mean?

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

#78

Post by jessriedel »

SideburnsOfDoom wrote: post #71
ourmandave wrote: post #69

Unanswered in article: How long does the power unit lasts until you have to replace the paper-towel-roll-sized U-235 core? Where are they going to put the old ones? What's the plug interface? Can I charge my iPhone? What about my electric razor? Are they going to test burying one in red sand for 15+ years and see if it can be dug up to phone home in an emergency?

And in 15 years, do you need to import a new core from Earth or what - have a uranium mining and refining operation up and running by then?

Enriched uranium is one of the few supplies for which it's probably economically sustainable to provide continuously from Earth.

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

#79

Post by imglorp »

ifdefdebug wrote: post #70

I find it frustrating NASA talking about putting people on Mars but if you look at reality, it can't even put astronauts in the orbit anymore. What about solving that problem first, and when it's done, then we can dream about Mars... Or are we going to outsource such mundane tasks like manned orbital space flight to the Russians and Chinese forever, while we are proudly preparing the colonization of Mars? /s

I find it encouraging the private sector is filling the gap. Musk's vision is clear if you assemble all the pieces his companies have built on Mars: solar and battery power, tunnel boring for both shelter, water, and air (which could imply return fuel he can do O2+H2).

Solar might not be the most efficient for Mars, but he can bring tons of it without messing with nuclear politics and PR. Note also the Boring Company TBM diameter is less than the BFS. Don't be surprised if a TBM one of the first payloads.

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

https://www.boringcompany.com/faq/

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

#80

Post by ethbro »

lostlogin wrote: post #38
sjcsjc wrote: post #32

Earlier quoted context omitted.

"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.

It was founded in North Carolina. The large number of freshwater waterways around there are generally known as black water.
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