Moon helium in fusion?

Aquamarine

Is helium a better alternative then the current proposed fuels for fusion reactors?

http://www.space.com/scienceastronom...m3_000630.html
http://www.asi.org/adb/02/09/he3-intro.html

Morbius

Aquamarine,

Helium would be more difficult to fuse than Hydrogen - there's more
electric repulsion with Helium than with Hydrogen. We also have more
Hydrogen than Helium readily available.

The one item in favor of Helium, is that if one uses Helium-3 [ available
on the Moon ], then the fusion reaction is "aneutronic" - it doesn't produce
neutrons - so it doesn't make other materials radioactive.

However, radioactivity is not an insurmountable problem - it can be
readily dealt with. The problems associate with getting Helium-3 from
the Moon, and bringing it back will probably dwarf the problems with
radioactivity.

Dr. Gregory Greenman
Physicist

Nereid

You know, nothing in either of the links Aquamarine gave tells us about the abundance (or difficulty of extracting) of He3 here on Earth (other than as a by-product of human activities). No doubt it's available here on Earth (otherwise, how would physicists have done experiments into its superfluid nature, for example?), and no doubt a minor component of the helium that's part of natural gas deposits. I suspect that if He3 were to become economically valuable, all kinds of entrepreneurs would find ways to supply the demand ... without having to go to the Moon to mine it!

Astronuc

Although the natural abundance of He-3 is very low (0.0137% in terrestrial sources), it can be obtained in relatively large amounts, as the product of the radioactive decay of tritium, which has been made for thermonuclear systems.

Of the tritium produced in the ten years following WWII (1945-1955), all of that, which has survived, has been through at least 4 half-lives, so more than 94% of it is now He-3. Of course, much of that may have already been used in experiments.

u235

He3 is an isotope heavilly bombarded on the lunar surface from solar waves (rays) which are tritated (not referring to water). This component can be used for propellant production however, lithium (which is almost abundent beaneath earth) is a more greater option.

- thus Li 6 - D is applicable for direct fusion propulsion, only after fission - because of thermal laws (millions of degrees).
D can be made from regular water - 1 in 6000 atoms are exising Dueterium /D.