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Lunar Helium 3 Could Meet Earth's Energy Demands
starannihilator writes "Helium 3, rare on the earth but abundant on the moon, may prove to be a feasible energy source with NASA's Moon-Mars initiative. Despite the American Physical Society's Report that the initiative harms science, the moon may actually benefit humans because it contains 10 times more energy than all the fossil fuels on earth. Long hailed as a potential source of energy, and outlined in detail by the Artemis Project, helium 3 may solve earth's energy crisis without any radioactive byproducts. The only problem: the reactor technology for converting helium 3 to energy is still in its infancy. Read more about the Artemis Project's information about fusion power from the moon here." Reader muditgarg points out that India has just hosted a global conference on Moon exploration and utilization, and adds a link to this related story on KeralaNext.
... is that the energy in question comes from thermonuclear fusion, and fusion can be done with terrestrial elements. We don't _need_ he3 to build fusion power plants; we can build them with deuterium/tritium fuel, or even just deuterium alone. Moreover, D/T fusion only requires plasma temperatures about a tenth those of D/He3 fusion. IIRC D/D fusion is also somewhat more attainable than D/He3 (and uses an incredibly abundant fuel available on Earth - deuterium is a stable hydrogen isotope available in quantity from seawater).
The only disadvantage of hydrogen isotope fusion is radioactivity. D/T spits out fast neutrons, while D/D can produce radio-isotopes (I think - someone correct me if I've remembered wrong). Neither technology produces hazardous nuclear waste however, and the radioactivity in question would be very short lived, cooling in decades to centuries, rather than millennia. Moreover, in D/T reactor designs, the only radiation is in the core itself, and said neutron radiation can be used to "breed" tritium fuel. Disposing of fusion waste long term, either by sealing the decommissioned cores, or storing the D/D reaction products, is easier than importing he3 fuel from the moon.
Erotic is when you use a feather. Exotic is when you use the whole chicken.
Problems:
- The concentration of He3 in the lunar surface may be very low. It could require processing many 100's of tonnes to get a gram/ounce/drop-in-the-ocean of He3. Of course, you could build an automated solar powered mining facility on the lunar surface to do it. You'd need serious $$$ though.
- Getting it back to Earth might be a pain. You could probably wrap it up in some aluminium projectile also mined on the moon, and fire it at Earth with a linear induction track or somthing. The projectile could have an ablative heat shield to protect the tiny precious cargo. More $$$ though.
- You need an efficient fusion power plant to 'burn' the stuff in and convert the heat to electrical energy.
Rather than using it on earth to generate electricity, it might be better used as a propellant for interplanetary spacecraft. The British Interplanetary Society once had plans for something called Daedalus which I think was designed to use He3 mined from the atmosphere of Jupiter. Is that even crazier?This is not a sig
1.) probably some international treaty says no-one owns it; however, as the saying goes, possession is 9/10th's... 2.) actually, it is renewable. The He3 actually comes from the sun... The moon surface just happens to be efficient at capturing it; and, is conveniently close. 3.) So? It's just 270M miles over that way.
First off, what happens if we strip mine that sucker and change its mass significantly? What are the chances of it being pulled in by the Earths gravity?
Consider how large the moon is.... Now consider the odds that we could change that in any remotely significant way by mining H3. Get back to me.
Oh, and while you're at it, go read up on orbital physics. changing the moon's mass would not in any way affect its distance from earth. What might affect it (again, in a very, very slight way) would be the rockets firing off from it to return the stuff to earth. Even if that does become a problem (which would likely push the moon away from us, rather than towards), just start launching from the other side and coming around.
I've got more mod points and GMail invi
Wouldn't need tons of material at those velocities. Inertial weapons have been theorized for quite some time: Pournelle and Niven's novel Footfall quite graphically portrayed the power of such weapons. In that novel, the hostile elephantine aliens simply orbited chunks of rock around our planet, each with a one-shot engine that could halt it's orbital progress upon command and allow it to fall to earth. A guidance system was attached that would allow the falling object to hit designated targets. A fifty pound rock falling from twenty-odd thousand miles can do a lot of damage and needs no explosives.
The higher the technology, the sharper that two-edged sword.
Indeed. The total stored energy of TNT is about 4 MJ (megajoules) per kilogram.
The kinetic energy of an object dropped from the Earth-Moon L1 point is about 50 MJ per kilogram. Adding explosives to any such device would be entirely a waste of time.
~Idarubicin