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I don't know if I've posted this to the right topic or not.
I've found two very good websites on nuclear propulsion:
http://www.newworlds.com/nucpro.html
http://www.nuclearspace.com/
I'm not an expert on anything dealing with this topic, but from what I've read, to me, nuclear propulsion is the best way to go as far as propulsion. It's been tested in the past and found to work. It has Isp(s) hundreds of times higher than chemical propulsion. We have the material available from nuclear missiles that are being dismantled. I don't want to turn this into a political debate but, with a majority Republican party in Congress and the White House, now would be the best time to try and get research and development started again. I know that the environmentalists are going to complain about a rocket blowing up in the atmosphere, but in the above listed websites, even if a reactor was in an explosion of a Challenger size it would not have received any damage or leaks. I would like to hear comments and/or complaints. Thanks.
One day...we will get to Mars and the rest of the galaxy!! Hopefully it will be by Nuclear power!!!
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You'll get no disagreements from me, TJohn!
Nuclear is the way to go, and the proonents of spaceflight must use this opportunity (the most pro-nuclear administration in many years) to restart development of nuclear space power / propulsion. NASA already has a limited space nuclear plan, but the future beyond building more RTG's is hazy.
I really lik VASIMR's prospects for powering the first humans-to-Mars mission. I'm not optimistic that Humans-to-Mars will take place before 2020, but that will at least give VASIMR time to mature. If NASA funds VASIMR, we will have an engine that will give us short (~100 days) travel times to Mars, low launch mass, and multiple abort options--all of which are ideal for human missions.
"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"
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So what do we need to do? Start a new "Operation Congress" campaign with a updated letter. I've sent out letters before but of course no response. Makes you wonder if the letters even get read by the politicians! But seriously, I think that we need to "kick it up a notch" on promoting nuclear propulsion.
One day...we will get to Mars and the rest of the galaxy!! Hopefully it will be by Nuclear power!!!
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We should take advantage of NASA's current nuclear friendly administration, Goldin was extreamly hostile to the thought of even RTG's, let alone propulsion. He frequently demanded non-nucler option be used, even if it ment the project could't be done.
VASMIR makes a good stop-gap measure until we can utilize something better, and it is not intrinicly linked with nuclear(although manned missions would use reactors) so will be easier to develope politically. VASMIR, however, still suffers from the curse of all known electric rockets, it has to slowly spiral out of orbit. This adds time not included in the transit times shown in reports. VASMIR is better then most adding only ~30 days to the outbound leg and ~10 days to the inbound one. I have not seen figures for capture times, so I am not sure how long they would be.
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I don't know if this is right, because I'm only a kid, but I've heard that the type of nuclear material used in nuclear propulsion wouldn't even be harmful if it was leaked-that it would sink to the bottom of the ocean.
Has anyone else heard this?
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Mission planners often try to divert a probe carrying plutonium RTGs into deep ocean waters to both avoid the RTG rupturing from hitting a rocky surface and to add an additional layer of protection against the toxic substance. Plutonium is dangerous if you inhale it as it just sits in your lungs and continues to irradiate them until cancer develops. I have nothing against using nuclear power in space but I think we should use other energy sources if at all possible and practicle.
To achieve the impossible you must attempt the absurd
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We are taking another look at nuclear energy. A technology with huge potential which keeps getting shelved despite an excellent safety record.
Very true. Even though we should use alternative sources of power if their practicle to use we shouldn't just outright ban or shun nuclear power. Everything has its place.
To achieve the impossible you must attempt the absurd
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the problem i see with nuclear power is not one of safety- in many years, there have been only 2 really major incidents, but one of disposal. with a half-life of around 88,000 years (if i remember correctly), the leftover isnt going anywhere fast. i dont think we can really rely on fission to power people, maybe spaceships, but not people. in fact, i would wait for fusion to power either, unless ion drives work well.
fusion produces a negligble amount of waste, and its theoretically much safer, so all the downside is really gone.
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Some see it as waste, but spent fuel can be reprocessed in fast reators into more fuel. Nuclear fission power is zero emmision and works well in the large scale, something few other low or zero emission power souces can claim. And I have seen the geology behind sites like Yucca Mountain, if it needs to be disposed of, it can be done safely.
In space disposal isn't a problem, the ship can always be shot into an solar trajectory on its final mission. Nuclear fission power systems and propulsion systems offer advanteges beyond conventional systems.
We would all love to use fusion power, but it won't exactly be ready within the next 30 years for space or land power purposes.
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Nuclear fission power is zero emmision and works well in the large scale, something few other low or zero emission power souces can claim. And I have seen the geology behind sites like Yucca Mountain, if it needs to be disposed of, it can be done safely.
This is one reason I'm very much in favor of Earthbased nuclear power plants. People are always afraid of the radioactive "waste" but they fail to realize that the crap being pumped into the atmosphere from coalburning plants releases significant amounts of radiation into the environment itself because of the uranium that is naturally mixed in with the coal. A nuclear powerplant is designed so that there is very little release of radiation into the environment outside of the reactor containment whereas a coal burning plants takes no measures to stop release of radiatio. And additionally, nuclear waste is far easier to deal with in a sanitary manner than trying to deal with billions of tons of coal ash that is often radioactive itself for reasons already mentioned. A handful of uranium will generate as much power as whole traincar load of coal. Now tell me which produces less waste? I should add to that unlike oil, uranium could keep us powered for thousands of years at current power usages if we were to employ breeder reactors to make more fissionables.
Waste is not an issue for space travel. The notion of polluting interplanetary space is comparable to polluting the ocean by dumping salty water into it.
lol, I like that analogy even though I think Soph was more worried about what to do with the actual physical waste rather than the radiation itself (which space is full of of course.)
To achieve the impossible you must attempt the absurd
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yes, but coal ash doesnt have the same 80+ millenia longevity as spent nuclear waste, does it?
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The urainium, thorium and other radioactive elements natualy in the coal does. Globaly coal plants dump 10000 tons of radioactive waste into the atmosphere a year, nuclear plants release a negliglble amount. Coal makes up over 50% of US electrical generation. You get over three times the radioactive dose standing next to a coal plant than a nuclear plant. Plus coal has the fun side effects of CO2, SO2, acid rain, etc.
Fusion may be the future, but that doesn't mean we shouldn't 'green' up our energy by going nuclear fission until it becomes a reality.
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then whats the big deal over southwestern nuclear waste?
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then whats the big deal over southwestern nuclear waste?
The problems aren't scientific or technical, they're political and emotional.
To achieve the impossible you must attempt the absurd
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Thanks for posting, NuclearSpace. I've been to your site many times. I hope you stay around so you can convince others about the benefit of nuclear power.
One day...we will get to Mars and the rest of the galaxy!! Hopefully it will be by Nuclear power!!!
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And besides radioactive elements (about 1 ton of U per million tons coal and an average 1000 MW coal plant burns 3million tons coal/yr.) coal emits heavy metals including lead, sulfuric acid, irritating sulfur dioxide, lung clogging particulates, carcinogenic chemicals like benzpyrene, etc. Millions of tons of sludge are produced every year that has to be dumped. Vast areas have to be strip mined. Transportation via RR trains, barges etc. leads to deadly accidents. Coal is really filthy.
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Are my eyes decieving me? Did I see NuclearSpace say that nuclear power is the only serious alternative to fossil fuels?
Thats... wholly innacurate.
Why, Iceland is going over to a hydrogen economy. Not a nuclear one - a hydrogen one. Germany is building a massive windfarm, and so is Britain.
So, no, nuclear power is not the only serious alternative. There are many other ways. And nuclear fission isn't safe; not by any stretch of the imagination. The only method of nuclear power that could be considered safe is fusion, and so far we've only boiled water with that, which isn't even as efficient as a coal power plant. And if you say nuclear fission is safe - just tell that to the kids dying of leukaemia in the areas around nuclear power plants.
Ex Astra, Scienta
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Why, Iceland is going over to a hydrogen economy. Not a nuclear one - a hydrogen one. Germany is building a massive windfarm, and so is Britain.
Unfortunately you need a source of power to extract the hydrogen and the rest of the world isn't as blessed with hydrothermal vents as Iceland is. If we're going to convert to a hydrogen economy (which I support) we'll have to get rid of our coal plants and replace them with something cleaner in order to extract the hydrogen. Like I said, Iceland is using hydrothermal for this. Hydrogen is more of an energy carrier rather than a raw source of power in that it takes a lot of energy to crack it from water or fossil fuels. Nuclear energy is perfectly viable for the task of producing hydrogen.
To achieve the impossible you must attempt the absurd
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There's other cool things you can do with that low-level radioactive waste, like mixing it into concreat or asphalt. It a way to dispose of it, and it could help the keep the roads from iceing, and could help the concreat to cure in cold climates or big pours.
In fact, now that I think about it, using radioactive waste to heat the concreat may help to solve some of the problems of pouring concreat on Mars (where it's realy cold).
He who refuses to do arithmetic is doomed to talk nonsense.
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This may be obvious to most here, but hydrogen fuel cells work by a chemical reaction between hydrogen and oxygen to produce water. Apollo used it as their primary electricity source, and the water produced was their drinking water. The Space Shuttle also uses fuel cells. One of the upgrades to the Shuttle was to replace the old platinum based fuel cells with proton exchange membranes. They new ones are cheaper, lighter, and produce more electricity per unit of hydrogen. If you want to use fuel cells for space, you will have to carry both hydrogen and oxygen to fuel it.
The fuel cells developed for cars use hydrogen and air as their oxygen source. Unfortunately not all hydrogen is reacted. They do have a recycling system that recovers unreacted hydrogen and feeds it back in. The exhaust is moist air and heat. The only question is where to get the hydrogen.
Hydrogen can be produced by splitting water into hydrogen and oxygen. If the oxygen were released into the atmosphere it would replace what cars consume, closing the cycle. Electricity could be generated in a number of ways: nuclear, geothermal, wind, solar, hydro (dams), tide harnessing, or coal burning. It wouldn't make sense to burn oil products to produce hydrogen; it would be more efficient to refine hydrogen from it directly. That is the other source of hydrogen fuel: refined oil. Hydrogen fuel cells would not put the oil industry out of business; they would just have to change their refineries to catalyze oil into hydrogen instead of gasoline.
The big advantages to hydrogen for cars are that:
1) Fuel cells convert more fuel into motive power and waste less as heat.
2) No toxic exhaust, this qualifies as a zero emission vehicle.
3) Electric generation can compete directly with petroleum.
4) Electricity can be produced when available and converted to hydrogen; the hydrogen can be used when needed. Often electricity power generation is at its peak at different times than demand.
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What makes nuclear power so special? In my mind, there are three things: energy density, no toxic chemical emissions, and dependability. Coal has a decent energy density and it can be burned 24 / 7, but it's too bad for us and our environment. Solar and wind, while the best for our environment, have poor energy densities, and they fluctuated based on the weather and time of day.
Energy density and dependability make nuclear power ideal for spaceflight. It will be much cheaper and easier to put a reactor or two on your spacecraft instead of the colossal solar arrays (see the Energia plan for putting humans on Mars.) And batteries would be needed when the sun goes down, necessitating the use of heavy batteries to store the excess power generated during the day.
It's time to cut the crap. Logic must emerge victorious over demogoguery. Make mine nuclear power.
"I'm not much of a 'hands-on' evil scientist."--Dr. Evil, "Goldmember"
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And if you say nuclear fission is safe - just tell that to the kids dying of leukaemia in the areas around nuclear power plants.
yes, and thats a good reason why there should be laws to keep nuclear power plants away from residential areas. who would live right next to a nuclear plant? im sure the same thing happens to someone living near a fossil fuel plant. this is a lame argument, and easily rectified.
And nuclear fission isn't safe; not by any stretch of the imagination.
based on what, things that happened 20 years ago? Nuclear reactor powered subs have operated for 40 years without a problem. one reactor leak and one explosion, decades ago, is not a bad record for a source of power that is exponentially better than fossil fuels. again, this argument is really not all that good.
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