NASA Wants to Send Nuclear Rockets to the Moon and Mars
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Re: NASA Wants to Send Nuclear Rockets to the Moon and Mars
#2How big is the added risk of toxic waste? I'm not sure how much waste is produced in relation to propulsion energy given but it must be quite small? And I imagine that during travel in space you could just dump that waste out into space considering the vastness of it all.
Re: NASA Wants to Send Nuclear Rockets to the Moon and Mars
#3How big is the added risk of toxic waste? I'm not sure how much waste is produced in relation to propulsion energy given but it must be quite small? And I imagine that during travel in space you could just dump that waste out into space considering the vastness of it all.
I don't know for certain but I'm fairly sure that the idea is that you don't activate the reactor until it's in space. Before a reactor is turned on the fuels are less radioactive. It's once you turn it on that radioactivity increases dramatically and you get all the nasty decay products and such.
So not zero but not as much as you might think.
Personally I don't like the idea. Environmental concerns are real, but those aside it's likely more expensive than multiple refueling flights with big conventional rockets. These would be expendable and very costly to research, develop, fuel, and launch, whereas for the same cost you could probably put stages in orbit and send fuel up to them with reusable tankers. Like hydrogen this is another example of NASA chasing the sexiness of high performance in a pure sense (high iSP etc.) without doing a total cost analysis.
In general SpaceX and Blue Origin have the right approach.
Re: NASA Wants to Send Nuclear Rockets to the Moon and Mars
#4For the first time, period. Doesn’t look like we had one 60 years ago...
Re: NASA Wants to Send Nuclear Rockets to the Moon and Mars
#5For the first time, period. Doesn’t look like we had one 60 years ago...
We did: https://en.wikipedia.org/wiki/NERVA
Tested successfully (on the ground) in the 60s.
Real pity about its cancellation, too. It was considered for the "Grand Tour" that the Voyager probes wound up doing; they could've sent nearly 30x the spacecraft mass with NERVA rockets.
Re: NASA Wants to Send Nuclear Rockets to the Moon and Mars
#6How big is the added risk of toxic waste? I'm not sure how much waste is produced in relation to propulsion energy given but it must be quite small? And I imagine that during travel in space you could just dump that waste out into space considering the vastness of it all.
I would imagine the engine would be fairly inert if it's not activated until in orbit.
I could see issues if the craft all of a sudden loses its orbit with an radioactive engine burning up in the atmosphere spewing radiation (although I'm sure we get bombarded with way more from the sun potentially?)
Maybe if during launch something goes catastrophically wrong and blows up mid-air like a bomb of sorts?
Re: NASA Wants to Send Nuclear Rockets to the Moon and Mars
#7How big is the added risk of toxic waste? I'm not sure how much waste is produced in relation to propulsion energy given but it must be quite small? And I imagine that during travel in space you could just dump that waste out into space considering the vastness of it all.
I don't know for certain but I'm fairly sure that the idea is that you don't activate the reactor until it's in space. Before a reactor is turned on the fuels are less radioactive. It's once you turn it on that radioactivity increases dramatically and you get all the nasty decay products and such. So not zero but not as much as you might think. Personally I don't like the idea. Environmental concerns are real, but th…
> "The massive amount of energy produced by these reactors could be used to sustain human outposts on other worlds and cut the travel time to Mars in half.
>“Many space exploration problems require that high-density power be available at all times, and there is a class of such problems for which nuclear power is the preferred—if not the only— option,”
It seems that nuclear reactors has more utility than simple power to weight ratio.
Re: NASA Wants to Send Nuclear Rockets to the Moon and Mars
#8An Arab country will be honored to host the Rocket launching..
Re: NASA Wants to Send Nuclear Rockets to the Moon and Mars
#9UFO's are real, the government just admitted it (someday they may even admit recovered ET craft), and yet the media is failing so hard at diving in deeper. Until the headline is "NASA now has working vehicles than that can warp spacetime" I just can't be bothered to get excited.
Re: NASA Wants to Send Nuclear Rockets to the Moon and Mars
#10How big is the added risk of toxic waste? I'm not sure how much waste is produced in relation to propulsion energy given but it must be quite small? And I imagine that during travel in space you could just dump that waste out into space considering the vastness of it all.
Whenever you're splitting Uranium atoms the results will tend to be radioactive. The results will build up in the fuel over time and eventually make the reactor stop working. Conventional reactors breed a bit of plutonium too as U238 captures neutrons but most aerospace reactors want to be as light as possible and so use highly enriched Uranium. So after your trip the engine will be quite radioactive but, as you point out, there's a lot of space and outside Earth's atmosphere and Van Allen belts it's moderately radioactive anyways.
Thankfully nuclear reactors aren't particularly radioactive until you turn them on, which is a big improvement on the radiothermal generators, RTGs, that we sometimes use in probes headed for the outer solar system where solar panels don't work. It's during launch, before this part gets turned on, that you have a risk of crashing and losing the reactor somewhere on Earth.