"Wet" Asteroids Could Supply Space Gas Stations 163
FleaPlus writes "Water ice was recently discovered on the large asteroid 24 Themis, and Space.com discusses proposals for producing fuel from asteroid ice. NASA and the President recently announced plans for robotic precursor missions to asteroids (and a human mission by 2025), as well as a funding boost for R&D to develop techniques like in-situ resource utilization. Since most of the mass of a beyond-Earth mission is fuel, refueling in orbit would be a huge mass- and cost-saver for space exploration (especially if fuel can be produced in space), but a large unknown is how to effectively extract water in an environment lacking gravity."
Another benefit (Score:3, Funny)
This could also provide good jobs for the inhabitants of these asteroids, serving Starbucks coffee and Cinnabons.
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I was trying to evoke the rest stops along the New Jersey turnpike. For the record, I do not live in New Jersey.
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I was trying to evoke the rest stops along the New Jersey turnpike. For the record, I do not live in New Jersey.
I was thinking airports as that is the only place I've seen a Cinnabon. Although, that would still be on topic as we are talking about space craft and a space craft refueling station would likely be like an airport.
And don't worry. If I lived in Jersey, I'd actively and preemptively deny it to.
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Are you trying to say that Starbucks is upscale? Wonder what 7-11 around is classed as where I live then, as Starbucks is too afraid to compete with them over average joe-coffee-buyer's money.
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I don't think the word you're looking for is "upscale". I think the word is "commercialized". Yes commercialized things can sometimes be upscale, but upscale stores generally don't have drive-thru windows.
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Just another reason why the chinese will beat us to it. There's never such a thing as too many chinese restaurants ;=)
(Good thing, too, too many of them in the US nowadays are following our business models; crap food, fast, cheap, filling...)
SB
Great! Im almost done.. (Score:3, Funny)
...training Ice Harvesting [eveonline.com]!!
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Try reading Pushing Ice instead - much faster!
Not so hard (Score:4, Funny)
a large unknown is how to effectively extract water in an environment lacking gravity
Easy, bring the asteroid down to earth to extract the water. I don't see why they have to make it so complicated.
Re:Not so hard (Score:5, Funny)
so instead of Armageddon in wich we try to destroy asteroids, we'll send up people/robots to make the asteroids land at the right spot?
and how big must these asteroids be to make it worthwhile? tektonic plate shattering big?
or will it be fuel negative? like the corn which requires almost as much diesel to harvest as it will produce?
or will you beam the asteroid to it's place with yet undiscovered tractor beams? risking urban catastrophes?
We'd simply put you under the landing site. The large "woosh" generated above your head would instantly slow the rock to 0 m/s.
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One step at a time.. (Score:3, Insightful)
I mean hell, the morons in Washington can't even decide if we should build any kind of space ship.
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You shouldn't!
Next question?
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> I mean hell, the morons in Washington can't even decide if we should build any kind of space ship.
I'm not aware of any substantial argument over whether we should build a "space ship" period, but the current spaceship argument divides up into three parts with multiple options each: crew launcher, crew spacecraft/capsule, and super-heavy cargo launcher:
crew launcher
* Ares I: the plan since 2008, set to be ready by 2017-2019 at a cost of $15-$45 billion (depending whose estimate you use). It's a liquid s
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That is because they lack both imagination and guts. Oh, and so do the citizens who elect them. Pretty sad end game for the country that prides itself (not entirely accurately) on a "pioneer heritage". Ftah.
SB
Mass Driver (Score:2)
It is probably incorrect to directly equate fuel with reaction mass. They can mostly be considered the same thing in a conventional rocket but if you could find another source of reaction mass then the fuel would only need to drive that mass away from you.
So I'm thinking that raw chunks of asteroid could become that reaction mass... pick up chunks of passing asteroid and throw them really really hard in the direction opposite to the one you want to travel in. Anyone following you might be in for a hard time
Water is reaction mass for nuclear rockets. (Score:2)
No need for electolysis. Just extract it and off you go. Methane, CO2, etc could be used as well.
Can we refuel from ice on Earth? (Score:2)
From TFA:
"... the water could be broken down into its component parts (hydrogen and oxygen) to make rocket fuel, experts say.
"Water is the main component in how you might make propellants," said Jerry Sanders, leader of in-situ resource utilization at NASA's Lunar Surface Systems Office at the Johnson Space Center in Houston. 'If you're going to go repeatedly to an asteroid, then the ability to basically start setting up gas stations could be extremely beneficial"
Hey, I love the whole space-gas-station idea
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I KNOW YOUR IDEA IS BRILLIANT BECAUSE YOU USED CAPS!!!11!!
I suggest that we start training porn stars as astronauts, since they're going to have to suck pretty hard to get the fuel all the way up the hose to orbit.
Extracting is the least of your problems (Score:3, Insightful)
the water could be broken down into its component parts (hydrogen and oxygen) to make rocket fuel, experts say.
Gee, sounds simple. Except that rockets generally run on -liquid- oxygen.
You are going to need one hell of an infrastructure to manufacture/store LOX, even more so for liquid hydrogen.
Theory and practice are pretty far apart on this idea, to the point where I would call it impractical.
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Gee, sounds simple. Except that rockets generally run on -liquid- oxygen.
You are going to need one hell of an infrastructure to manufacture/store LOX, even more so for liquid hydrogen.
Theory and practice are pretty far apart on this idea, to the point where I would call it impractical.
To get good fuel density they will generally want liquid fuel. But getting it to liquid is just an engineering problem. Space of course is rather cold, but there is no air for convection transfer, and few solid bodies for co
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Cooling things in space is easy. Shield your storage from the sun, put radiator panels on it, and eventually it will get down to a temperature somewhat close to the microwave background of the universe, about 4K, depending on what other radiative sources you can't shield it from. The more radiative surface area you have, the faster it'll cool down.
Vacuum is an excellent insulator.
SB
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Cooling things in space is easy.
Cooling things in space is hard. The rest of your post is correct though, assuming at least that your radiator is completely insulated from solar radiation.
The thing is, radiation takes a very, very long time to transfer energy because it is very slow until you get up to much higher temperatures, like where incandescent bulbs operate. It's a T^4 process, so as as the temperature halves, the rate of energy transfer decreases by a factor of 16. If you try to get to 4K direct
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Ah, can finally answer. For some reason haven't been able to reply to anything today, just hangs.
I'm aware of how slow radiative transfer is, I aced every physics class I took twenty years ago... The way around that isn't using a coolant transfer system - unless you are really in a hurry, that's how we have to do it here on earth - it's to shield a large mass from solar input, put a lot of radiative fins (or anything else with more surface area, there are lots of ways to do this) until it's
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Do you understand any of what you just said? Hydrogen is fuel because you react it with oxygen to produce water. If you split water into hydrogen and oxygen, then combine it again, you get less energy than you started with. Doing it 'RIGHT HERE ON EARTH' would be a pointless waste of energy for most uses.
It's useful in space because they don't need energy, they need rocket fuel. A solar array on an asteroid can work 100% of the time, creating rocket fuel. This is how you create rocket fuel on the grou
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The whole point is to have extracted fuel outside of the Earth's deep gravity well, so you don't have to waste launch mass putting it into space.
Have we learnt nothing? (Score:3, Funny)
Really? (Score:4, Interesting)
IANARS, but "extract water in an environment lacking gravity" doesn't seem like that hard of a problem.
Water's a fairly easy substance to deal with - nonexplosive, liquid at easily reachable temps, possibly bound in the asteroid in nothing more significantly complex than an ice conglomerate.
Crushing/pulverizing the regolith and then tossing the mess into a gentle screen centrifuge with even moderate heating (ie above 0 deg C) would seem to do the trick - the water would just flow out the centrifuge walls...wouldn't even have to be 'batched' but could run as a constant process. The spin rate wouldn't even have to be significant, just enough to let inertia do its thing and force the water from the slurry.
At least to my ignorance, this seems at least an order of magnitude LESS difficult/dangerous than electrolysis in zero-g, something we've (AFAIK) got a pretty solid grasp of.
What am I missing?
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[snippage 'its so easy to do'.]
Among other things? Dealing with the waste once you've extracted the water. What if it's abrasive? Or chemically reactive? Or what if there is outgassing that dissolves in the water? Heck, what if there are solids that dissolve in the water? Etc.. Etc..
That's just some of the potential problems in the centrifuging step alone. No obvious showst
Exactly (Score:2)
This is the thing that always trips up the /. crowd. Making a few wisps of O2 and H2 via electrolysis in space is one thing. Making volumes of liquid O2 and H2 sufficient to actually power rockets that go somewhere is an entirely different story. It's going to require a simply enormous amount of infrastructure, all of which would have
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> What am I missing?
I think the difficulty is having an automated system capable of doing everything you described, that can produce sufficient propellant to be worth the initial investment of launching everything to the asteroid, powered only by solar cells or an RTG. I suspect the problem of harvesting the regolith without accidentally sending your harvester flying from the asteroid is also pretty tricky.
extracting water (Score:2)
but a large unknown is how to effectively extract water in an environment lacking gravity."
With a silly straw, Silly!
Lots of water and hydrocarbons in space (Score:2)
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Heck, I'd be willing to pay for it as long as it is open source.
asteroid mining a la slashdot (Score:2)
OK, so, water is just the ashes of oxygen and hydrogen burning together, OK?
Burning together roughly the way we burn them in conventional rocket thrusters.
So, in order to succeed, the recipe will be:
1) get to icy asteroid, mine it, get water
2) magically turn back the water into its original components, before burning: O2 and H2 (???*)
3) burn them again together in your thrusters, and profit!!!
(*) yes, you can use a solar panel. Just let me bet that the mass of solar panel + water extractor + electrolysis ap
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Just let me bet that the mass of solar panel + water extractor + electrolysis apparatus is larger than the ordinary, earth-brought mass of fuel that'd bring the same thrust.
If you're thinking of this as a one-off thing, then you're probably right. But once the equipment is up there, it can stay up there and keep producing fuel. So we could seed suitable asteroids with fuel plants and let them sit there, making fuel, to act as "gas stations" for later stops.
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OK, touché
not just rocket fuel... (Score:2)
but also fuel cells to drive the various electrical systems onboard.
That is, unless the plan is to lift a nuclear reactor out there, as is used in submarines.
Not just water (Score:2)
Come on now, these concepts have been bandied about for literally decades. I read about this when I was a kid more than three decades ago.
The mineral wealth contained in the asteroids of the solar system is literally incalculable. It's been estimated that one mid-size near earth asteroid (say a few km in diameter) of the proper composition probably contains enough metals to supply the world's demand for decades. It's all out there for the taking, along with plenty of free energy, and it's
Panspermia (Score:2)
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Maybe you should seriously consider leaving afghanistan and iraq, then rejuvenate your lousy economy, ain't it?
Do you have to actively work to create sentences like this? Is there some kind of system of analysis and theory behind poor sentence construction that you employ? I can't imagine anyone would actually be able to write like that without concerted effort and thought put into it, and yet you trolls do it every day. Perhaps it is an under-appreciated art.
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Maybe you should seriously consider leaving afghanistan and iraq, then rejuvenate your lousy economy, ain't it?
Do you have to actively work to create sentences like this? Is there some kind of system of analysis and theory behind poor sentence construction that you employ? I can't imagine anyone would actually be able to write like that without concerted effort and thought put into it, and yet you trolls do it every day. Perhaps it is an under-appreciated art.
You would write something like that - in one of the Scandinavian languages.
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The whole topic is nonsense. They can't even pull oil from the Gulf floor without having a disaster.
I love to bag the Yanks as much as the next guy, but I'd like to point out that it's BP (British Petroleum) that can't even pull oil from the Gulf floor without having a disaster.
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I meant the earthmen...
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* kind of like playing 'quarters' by hitting a cup racing
Re:Mining Asteroids like Eve Online (Score:5, Informative)
if landing on an asteroid is difficult at best*, and the chances of the asteroid moving in the direction of your ship's travels are slim to none
Why do you assume either of these? Asteroids are orbiting the sun. Their orbits are predictable, modulo some minor variations caused by the (very weak) gravity of nearby ones. It's much easier than, for example, landing on an aircraft carrier, where you have to worry about changes in the wind.
As to the probability of them travelling in the same direction, it's pretty much guaranteed. If you're going from the Earth to the asteroids, you use a transfer orbit, where you are starting in the Earth's orbit around the sun and then injecting enough energy to move you out to the asteroid belt. You end up on solar orbit in the asteroid belt. Any asteroid in the same orbit will, by definition, be going in the same direction and speed as you. Asteroids in nearby orbits will have a small relative speed, and the energy required to enter a transfer orbit to rendezvous with them is relatively small.
More important obstacle... (Score:3, Interesting)
Whether or not landing on asteroids is easy (I have my doubts - their motion is likely to be at least somewhat chaotic), there's a more important problem. We're talking about water here, which doesn't, you know, make a very good rocket fuel. Being as how it's already oxidized and everything. TFA indicates that for this to work, you'd first have to grind up some substantial amount of ice-containing rock, microwave it for a while, separate and purify the water... and then you get to electrolyze it. In other w
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You could, maybe, pack them into a compact ball, and shoot them back at Earth? And then we'd pay you? You'd just have to make a point of only landing on sufficiently mineral rich asteroids.
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Half baked?
We could do it with current technology. It's just rockets and mining equipment on a massive scale.
Sure, there are problems to be worked out (I can think of a few dozen right off the top of my head, but these are elsewhere on the web and it'd be a waste of time to list them here) but it's not like we would have to invent some entirely new technology just to get a start at it.
Sigh.
Sooner or later we have to start thinking about this seriously. The resources o
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We're talking about water here, which doesn't, you know, make a very good rocket fuel.
You're quite correct that it would take a large amount of energy to harvest water, probably more energy than it's worth, but just what do you think it is that they keep in that really big fuel tank on the belly of the Space Shuttle? [wikipedia.org]
The main function of the Space Shuttle external is to supply the liquid oxygen and hydrogen fuel to the Space Shuttle main engines. It is also the backbone of the launch vehicle providing attachment points for the two Solid Rocket Boosters and the Orbiter. The external tank is the only part of the shuttle system that is not reused. Although the external tanks have always been discarded, it is possible to take them into orbit and re-use them (such as for incorporation into a space station).
Water is H2O, hydrogen and oxygen, after all.
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You'd also need to figure out how to dispose of your rock tailings in such a way that they don't produce a giant abrasive cloud around the asteroid you want to work on
Control your tailings output, and use solar collectors to fuse it into aggregate masses you can use for mass shielding. That's just one idea. You could also collect it and use it in rocket engines if it's fine enough, although that would likely require more energy input than it's worth.
In any case, any cloud that it formed aro
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That only applies to solo flying, what if it will be a formation flight?
I see what you did there.
If the universe were a internet spaceships game (Score:2)
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Except for the fact that right now it is that much easier to mine from earth, or recycle a lot of the material. We don't need to mine from space until we are actually up there for a while.
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Great, now we're going to have environmental disasters in outer space.
Don't you need to have an ecology first, before you can have an environmental disaster?
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No. All you need is an environment to have an environmental disaster.
And space, harsh as it may be, is an environment.
And if there's a way to spoil it, humans will find it.
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And space, harsh as it may be, is an environment. And if there's a way to spoil it, humans will find it.
And space, harsh as it may be, is an environment. And if there's a way to spoil it, Exxon Valdez and BP will find it.
Fixed it for you.
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Yeah--as soon as they get to that first asteroid, they'll plant a couple shrubberies with a nice two-level effect and little path down the middle...
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No. All you need is an environment to have an environmental disaster.
And space, harsh as it may be, is an environment.
No, that's not true. You're simply wrong about the definition of "environmental disaster". It is an ecological term which doesn't make sense in environments that don't have life present.
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OK, you win.
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I am sure BP has a very save solution for the extraction of 'fuel' in space.
Sure they do, it's just the "containing it" part that still needs a little work.
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For example, to break up water into Hydrogen and Oxygen, you can use
...solar radiation, which costs you nothing, and the interesting parts of which can be gathered with a large mylar-bag mirror.
The rest of your comment was dumb after I changed this part, so I ignored it.
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The rest of your comment was dumb after I changed this part, so I ignored it.
Maybe you shouldn't have. Hacker made some very good points that had nothing to do with the energy source itself. Namely, that there would need to employ incredibly sophisticated materials and engineering science to build any kind of long term functioning electrolysis system that (I assume) would need to operate semi-autonomously with minimal maintenance.
The power source of this system seems like the easy part.
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Maybe you shouldn't have. Hacker made some very good points that had nothing to do with the energy source itself.
No, he did not. All of his points were related to the energy source except for compression of the fuel or they're just staggeringly, stupidly wrong. For example, "Or you're going to need a very large and complex solar collector with super-complex metallurgy to generate a high enough heat to disassociate the water." No, that's completely incorrect. You can use ordinary mylar to reflect sunlight, even in space. No complex metallurgy is required. The complexity is very low as well because fine aim is not requi
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>No complex metallurgy is required.
Hows about the issues involved in building a a target that can stand the white-hot temperatures needed to dissassociate water, and keep it from melting down and reacting with the oxygen, sulphates, borates, and other contaminants. White hot steel does not last long in the presence of pure oxygen and sulfates.
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Hows about the issues involved in building a a target that can stand the white-hot temperatures needed to dissassociate water,
The asteroid is the target.
and keep it from melting down and reacting with the oxygen, sulphates, borates, and other contaminants.
The asteroid is parked and given a steady spin. It's shielded from the sun, which allows its temperature to equalize. Then it's heated in a controlled fashion... You get the rest. It might conceivably be necessary to carve them into convenient pieces first, but this is hardly proven.
White hot steel does not last long in the presence of pure oxygen and sulfates.
As the asteroids are heated, different materials will "cook off".
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>As the asteroids are heated, different materials will "cook off".
Sorry, I added to the confusion. I was alluding to the improbability of making a solar disassociator-- the thingy that splits the water. It has to run white-hot to split water.
You're talking about a solar cooker, in order to heat the asteroid and drive off the water. Totally different thingie, and I wonder how you'd ever collect the water? Hmmm....
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Once you've got water, if you can figure out how to contain it, you can use it as the target for the sunlight, too. Your problem then will be reflecting the energy lost as radiated IR back onto it. So obviously the hard part is containing it. Currently I am imagining a very, very large spherical balloon with a single-angstrom layer of aluminum painted on a big circular portion of it as a reflector. Similar technology on a much smaller scale (yes, I do enjoy a good understatement) is currently used to produc
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So, now all we have to do is build an incredibly large and thick pyrex sphere. Millions of miles from earth. And let it hang around in the asteroid belt (which, needless to say, is full of flying rocks) without breaking. Yeah, that'll happen.
Even if there was any possibility of that working... now you have a sphere full of white hot oxygen and hydrogen. How, pray tell, do you get them out without them oxidizing again? How do you pressurize/liquefy them?
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The Mylar solar mirror could be aimed at Titanium Oxide solar assisted electrolysis, making that process even more efficient.
Water would be prefiltered using existing NASA water filtering technology in use on the ISS now.
But what really strikes me about AH's answer is even with his engineering challenges which are overcomeable, and horrible energy to fuel ratio guesstimates.
This Rocket fuel assembled in space 24/7 in the asteroid belt would likely still be cheaper than if we created the fuel on Earth, and f
Re:Mostly laughable concept. (Score:4, Interesting)
Even your unmanned probes would work better with an unmanned fuel depot halfway to anywhere.
And no under our feet does not work, only a tiny percentage of the Earth's crust is mineable. And we've gotten all of the easy stuff already, if you look at how many tenths of an ounce per ton is considered profitiable for miners that then use acid solutions to reduce the ore down to what they want, and tailings (the waste) you end up with tons of industrial waster per ounce of useable material.
It has gotten so bad that many companies are now using current technologies to reprocess the tailings of mines/plants closed in the 1970s because those leftovers are richer in what they want than the new mines they are finding.
There IS more raw material in the belt than all of the Earth, and at higher concentrations than any mines being operated anywhere on the planet.
Now, tell me if you really believe what you've said, how much Helium / Helium 3 there is here on Earth, under our feet? What is the cost per ounce?
Helium 3 is $46500 per troy ounce.
Helium we get from Nuclear decay, Helium 3 we get as a byproduct from manufacturing Tritium for Nuclear bombs, we haven't made it in industrial quantities for a while, but there are numberous Medical Imaging and Fusion research uses for this limited resource.
How much is there on the moon?
How many Rare Earth Elements are available in the Belt that would make more efficient magnets for Hybrid Cars and High Speed Trains, but Neodymium is about $1 per Gram, and the price will go up the more demand for Hybrid and Electric vehicles goes up.
How many CD players and Cell phones would you have to recylce the magnets from to come up with the Kilo of Neodymium used in the motor of 1 Prius?
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how much [Helium 3] is there on the moon?
Not enough to be worth mining. At about 0.01ppm, you need to mine a hundred million tons of lunar regolith to get one ton of Helium 3, this doesn't even begin to count the energy required to extract the helium.
It's basically pointless to mine, you'd spend more energy extracting what little there is than you'd get from using it as fuel in fusion reactors we haven't even invented yet. Nevermind the logistics required in mining a hundred million tons of rock on the MOON.
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>..solar radiation, which costs you nothing, and the interesting parts of which can be gathered with a large mylar-bag mirror.
Yep, in superficial theory at least. The tricky bits involve shaping the mirror to the required accuracy, aiming it, and building a a target that can stand the white-hot temperatures needed to dissassociate water, and keep it from melting down and reacting with the oxygen, sulphates, borates, and other contaminants. White hot steel does not last long in the presence of pure oxyg
More thinking needed here... (Score:2)
Ok, so I build the giant mylar bag mirror, and focus a bunch of sunlight onto the surface of the asteroid. What do I have now? Hot rocks with the water ice vaporized out of them and escaping into space. Even if you could somehow focus enough solar energy onto the surface to actually electrolyze water (without actually vaporizing the rock substrate), you've not even postulated a way to collect the product.
If you were planning to do something different with your reflected sunlight, it wasn't obvious from you
Cooling Systems (Score:2)
Correct me if I am wrong, but cooling systems should be far superior in space, too, or not?
I mean if you shield away sunheat with your solar collectors, behind that it should be pretty cold, or not?
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>Correct me if I am wrong, but cooling systems should be far superior in space, too, or not?
Not.
There is nothing there to conduct or convect the heat away, such as the running water that we use to cool power plants down here.
All you're left with is the option to radiate it away, for which you require huge amounts of surface area of highly heat-conductive material. The deployment of several square miles of unobtanium is left as an exercise for the reader.
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Water gets frozen in space, does it not? therefore cooling the water would be possible by transporting it away? Sorry, I never was in space and did not study astrophysics, therefore I only know
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Multiple citations needed.
I don't know where you pulled those numbers out of, but they're completely wrong. Depending on the process used electrolysis can have an efficiency rating of 30%-60%. Nuclear reactors are much better than 20% efficient, unless you think an RTG is a nuclear reactor. Solar thermal power is a better bet for generating large amounts of power for running a space factory. No fuel needed and a few square kilometers of mylar will set it up nicely.
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> Depending on the process used electrolysis can have an efficiency rating of 30%-60%.
Citations needed. One has to differentiate among the THEORETICAL electron-volt efficiencies, and actual efficiencies. The numbers you gave are the theoretical ones.
>Nuclear reactors are much better than 20% efficient.
A ground-based nuke plant with unlimited weight and space and maintenance and unlimited heat-sinks to a cold river, yes those, when running, and watched over by hundreds of humans, yes, they can hit 30
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IANARS, but I've always thought that in space, there was plenty of energy to be harvested from the Sun, via solar panels, or directly applying the radiation as another poster commented. From what I understand, the reason we require so much fuel is because we need more than just energy, we need something to push behind us, which is why ion propulsion is popular for long distance space travel. You use what little mass as effectively as you can. We're not trying to run a power plant here. Of course we're not g
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hydrogen is a joke
Your analysis is a bit simplistic and doesn't take everything into account.
Hydrogen, as it's proposed to be used in cars, is an energy storage medium that can take the place of big, heavy batteries that take a long time to charge. While you're absolutely correct that it's less efficient than converting electricity directly to motion, it becomes a more viable option when you factor in the weight and inconvenience presented by current (no pun intended) battery technology.
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use it in balloons
oh no, wait...
oh, the humanity!
Or this. [outlandishpodcast.com]
In any case, gasoline has far more stored energy per pound than hydrogen does, yet we're all driving around with fifteen gallon or so of it in our cars.
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I agree that batteries would be better in the long run, if the technology gets to the point that they're viable. Hydrogen is a good interim solution, however. Will it solve all our energy problems? No. But it's better than what we have now.
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wouldnt the energy given off by the thrust in a nuclear reactor be radioactive?
Re:Water for Life, Nuclear for Fuel (Score:4, Informative)
Basically, no.
In somewhat more detail, slightly. Reactor coolant tends to get radioactive after a while. But a nuclear rocket doesn't have any particular part of the coolant present for "a while", since it goes in one end and out the other without any potentially embarrassing recirc.
So, in general, if you used H2 as the reaction mass for your reactor, you could expect some non-radioactive deuterium moderately (which is a joke, in case you didn't get it) regularly, and an atom or so of tritium now and then.
If you used water, the same plus some O-17 and less often O-18.
Note that the amount of radioactive H@ (and O2) will be dependent on the reactor design. Some neutrons are easier to capture than others....
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But aren't we wasting time trying to create liquid fuel in space if nuclear is a more feasible solution?
I'm making this up (feel free to correct me!) but I would imagine that water is more plentiful in comets than usable nuclear fuel is and would be easier to mine.
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and what would that do to the tides?
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Space Colonies of course.
Which despite their engineering challenges will be easier to build than to tell people not to have more kids.
Re: (Score:2)
what you need is a forge, a metal shop, a greenhouse, living quarters, a large solar concentrator array, a sizeable asteroid with ice in it, and you could probably bloody well live on the thing.
Assuming there are enough nitrates available on the asteroid to allow you to grow stuff, anyhow. I have no idea whether or not the "soil" you could obtain from an asteroid would have enough usable nitrogen to support plant life. If not, you might have to bring some with you from Earth and have it replenished occasionally.