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NASA Seeks Nuclear Power For Mars (scientificamerican.com)
New submitter joshtops shares a report from Scientific American: As NASA makes plans to one day send humans to Mars, one of the key technical gaps the agency is working to fill is how to provide enough power on the Red Planet's surface for fuel production, habitats and other equipment. One option: small nuclear fission reactors, which work by splitting uranium atoms to generate heat, which is then converted into electric power. NASA's technology development branch has been funding a project called Kilopower for three years, with the aim of demonstrating the system at the Nevada National Security Site near Las Vegas. Testing is due to start in September and end in January 2018. The last time NASA tested a fission reactor was during the 1960s' Systems for Nuclear Auxiliary Power, or SNAP, which developed two types of nuclear power systems. The first system -- radioisotope thermoelectric generators, or RTGs -- taps heat released from the natural decay of a radioactive element, such as plutonium. RTGs have powered dozens of space probes over the years, including the Curiosity rover currently exploring Mars. The second technology developed under SNAP was an atom-splitting fission reactor. SNAP-10A was the first -- and so far, only -- U.S. nuclear power plant to operate in space. Launched on April 3, 1965, SNAP-10A operated for 43 days, producing 500 watts of electrical power, before an unrelated equipment failure ended the demonstration. The spacecraft remains in Earth orbit.
No, troll, this isn't simply using 1960s technology. I understand the sarcasm in your post, but I still see that you're a troll.
There are challenges with fission reactors in space that don't exist on Earth. Specifically, you have to cool the fuel to prevent a meltdown. On Earth, this is accomplished by pumping large amounts of water through the reactor. The steam is used to generate electricity, but it also keeps the fuel cool. We generally build nuclear plants by bodies of water such as rivers, and the excess heat is transported downstream. There isn't an easy solution for dissipating heat in space. There isn't such an easy way to use conduction, convection, and advection to dissipate heat.
It's worthwhile to figure out how to do this, but it's not simply using 1960s technology. You, sir, are a troll trying to draw out people to argue with you.
No, NASA is very sane and totally right to use nuclear power for this use case. Nuclear power for earth side, widespread usage is utter lunacy due to the eternal waste, the immense costs and lastly the inherent incalculable dangers. Idiocy like thorium reactors and reprocessing are insane, not this.
For a small bootstrap colony or a science station on mars, nuclear power is by far the best option right now: proven and fairly reliable, small (think reactors from subs), easy to transport and set up (you have to insert the fuel rods on mars, transporting a mostly inert reactor). These small reactors are then used to build the infrastructure and bootstrap industry on mars so they can produce their own industrial base with solar power cells or hopefully fusion power or whatever else one can use on mars.
So as long as the nuclear reactors are limited in power and numbers, this is the exactly right solution until fusion reactors are possible.
Going to Mars makes no sense anyway, it's just another flag planting exercise. Mars is the politically stated goal for NASA because anything else requires 5 minutes explanation to idiot politicians who require "announcables".
Stating that their goal is Mars satisfies that requirement and allows them to spend money on developing heavy launchers, technology for in situ resource utilization and other technologies for long duration missions.
One of the few upsides of a manned mission to Mars is that we can send all the infrastructure there before the trigger is pulled to lift any humans off of Earth. We can make sure it arrives safely, and works, rather than having to send it on the same trip as the astronauts. Even if the solar cells, ice purifiers, and hydroponics work at a rate too slow to keep up with human consumption, they could be designed to operate when noone is there, to stockpile enough resources to last the duration of a human visit. Food silos, batteries, water tanks, and a habitat can be sent and filled up beforehand. Assuming everything but the seeds were sterilized, I wonder if the resultant food could be preserved indefinitely on Mars; ya know, until the humans show up and spread their microbiome everywhere.
If a colony is dependent on regular shipments of fissile material, that could cause problems, particularly if a shipment blows up/gets its launch delayed, or if the colony desires independence. Hawking et al suggest that we should get a Mars colony in part so that we wouldn't be doomed by a third world war; however, if said colony belonged to one of the major world powers, it's much more likely to be targeted. China already has tested weapons that can destroy satellites, I wouldn't put it past them to use a weapon that would destroy their enemy's Mars colony.
Corruption is convincing someone that the selfless ideal is the same as their selfish ideal.
The bigger issue isn't the possibility of and potential costs of nuclear incidents. Rather, it is nuclear waste management.
As a power source it's competitive if you only factor in power production and rudimentary waste management like we're doing now. But that completely falls apart if you consider the future costs of storing the nuclear waste over hundreds of thousands or millions of years.
Where do you think Uranium comes from in the first place, the magic nuclear tree? It comes out of the ground. There is zero reason not to put the spent fuel back into it.
"Processing the uranium out from the ore compounds is a lot of effort. Why do you think it's easier to put it back into those?"
Care to point to where I said that? Save your lame straw men for a student debate.
"Or do you think you could just grind all the waste up into fine dust and sprinkle it around?"
No, you put it into a stable borosilicate glass substance that its stable for millenia.
"It's also no longer just uranium. If it were there would be no need to get rid of it.
Additionally anything that has been near the reactor for any length of time is also radioactive waste including the reactor itself."
The total radiation levels will never be greater than what came out of the ground in in the first place. If they were we'd have invented a perpetual motion/power machine. All solid waste can be stored and liquid waste can be evaporated and stored. So long as its a long way from a water table waste is safe to store underground.
What happens in 100K years you ask? Who cares quite frankly. If we don't get CO2 output down there won't be much of an enviroment in 1000 years to worry about, never mind 100K, and nuclear is one of the best ways to achieve this.
You need to enrich the stuff for it to be useful in a reactor (or for that matter, a weapon). You can't just shove the result back into the ground and expect it to be as benign as the naturally occurring stuff. Not to mention Plutonium and other nuclear waste, which you don't want anywhere near a water supply.
Research & exploration are NASAs main missions and there is a need for around 500Kw in order to produce Methane & O2 for return flights from Mars that would be difficult to produce otherwise (at least on initial missions).
Spending billions on ILS launchers that have no mission is insanity (though Nasa spends the money it's the Senate that directs them to do so and micromanages the budget so that they must spread it around all 50 states).
It's interesting that the SNAP-10A is still up there as almost all opposition to the use of reactors in space is "What it it crashes on launch" by people that refuse to believe that we can build containment vessels sufficient to not spill the reactants even after a failed launch. I wonder, given that SNAP-10A is already in orbit, and didn't stop working due to any fault of the reactor itself whether it's fuel could be recovered to power a modern reactor. Probably not as it certainly wasn't engineered to to be disassembled easily, especially in space and things like vacuum welding may be an issue but it'd be a great hack if they could.
Democracy is a sheep and two wolves deciding what to have for lunch. Freedom is a well armed sheep contesting the issue
http://www.nytimes.com/1989/06/24/business/patents-nuclear-battery-converts-reactor-waste-products.html
http://www.rexresearch.com/nucell/nucell.htm
http://autoweek.com/article/car-news/strange-life-and-stranger-death-paul-brown-case-another-smart-guy-doing-dumb-thing
I am the unwilling control for my Origin.
Here's my conspiracy theory.
While they may see potential value for Mars, I see this as a way to acclimatize people to the idea that nuclear is a safe option. Where NASA is in the industry and previous accidents aside, the American public, as a whole, still regards NASA as being the same, awesome NASA that it was in the 50s.
That being the case, if this can bring nuclear into the public consciousness as something that's good and safe and useful, then it won't be about Mars, it will be about how we can "leverage what was learned from developing reactors usable in the harsh Martian landscape for use safely at home".
Take it to the limit, everybody to the limit, come on, everybody fhqwhgads.
If a fission reactor crashes on Mars, presumably the planet itself will break into a group of extremely radioactive fireballs which will then collide with Earth and kill us all. Is that what the 70 years of nuclear paranoia sci-fi has you thinking?
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I wonder if Trump is secretly a steam punk?
A coal power spacecraft with gold trims, and hardwood frames.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
That drawing off of heat is not just "to prevent a meltdown." The heat represents the output energy itself, which to be efficiently converted into electricity has to be dumped into as low-temperature a heat sink as possible. We use large bodies of water as heat sinks on Earth for ALL thermal power plants because the temperature differential is the greatest.
Why would NASA put effort into Uranium reactors when Thorium is so much more promising? It doesn't get more "do-over" than an entire fucking planet.
Because thorium designs have to be developed and proven out on Earth first. The ORNL work was just a proof of concept, not an operating commercial reactor.
It will never happen. At least not for a very very very long time. We have many places on earth that are not possible to be independent right now that are magnitudes easier and more habitable.
If they really want to play around, they should try it here on earth first as a proof of concept, preferably long term. The whole failed biodome experiment being a good example. Heck, put in the the Arctic or Antarctic and see how it fairs, or even just a very harsh remote region. Probably also be magnitudes cheaper to try that anyway. Heck turn it into a reality show and maybe it'll pay for itself these days...
"Nuclear waste" is a bit of a misnomer, from what I understand a VAST majority (I think like 95%) of what we term as nuclear waste is still perfectly usable fuel, it is simply contaminated with highly radioactive components. Those components can be removed via reprocessing, which most countries do. Once that is done the actual waste is far more compact and radioactive for far less time. The US however sabotaged its own reprocessing program by banning it back in the 70s, and then wrapping the industry in obscene levels of red tape that effectively prevented most new projects.
"The water will destroy the facility were the glassed stuff is stored. The glass could then be crushed by cave ins."
Uranium ore in the ground has been eroded by rivers for eons. It hasn't poisoned the planet yet.
"I just don't think the dump the waste in a hole and forget about it approach that is used in most cost calculations is viable."
Actually, you can do just that thing. It is just a matter of how deep you want to put it. An we have the technology to do it.
In short, you drill a hole in the convergent boundary between two plates. Preferably out in the ocean somewhere. I think two miles down under the sea floor is what I saw in a paper.
You put the waste on the downward plate. Plate tectonics will carry the waste holes down under the ascending plate, down into the planet where it will be "cooked" for the next few million years.
The point being that this will be deep enough to be completely out of the biosphere. Once the wastes starts its downward journey then you can effectively forget about it.
Any disaster that is great enough to bring it to the surface after a few hundred years , well put it this way. Having a few tons of ancient toxic waste coming to the surface will be the least of your problems.
Sure the description here is a highly simplistic summary but that is the basic ideal.
I read at +2. If your post doesn't reach that level I will not see or respond to it.