does anyone know much about this? it looks like it has the potential to be the next big energy source...it has been talked about for years....

This may help you.
Travelling in space requires the generation of thrust. This thrust has varying effects on the spacecraft, depedant on the mass being ejected and the velocity of the ejacta. This is basic reaction mechanics (momentum), and is defined by the following equation (Newton's Third Law):
Newton's Third Law Applied to Rocketry
mshipvship = (mship-mejecta)vship + mejectavejecta
Where v is a vector quantity. Thus, the greater the value of vejecta, the greater the increase in vship.
Since a ship is limited by its reaction mass, the best way to get increases in velocity are by somehow propelling the ejecta at faster rates. The resultant atoms and subatomic particles from nuclear fusion can be ejected at more than 10,000 Km/s, much faster than any chemical rocket ever could.
The Basics of Helium3 and Deuterium Reactions
Hydrogen is the most abundant element in the universe, and can even be found in interstellar space. Normal Hydrogen has 1 proton and no neutrons. Deuterium is an isotope of Hydrogen that has a neutron next to its proton.
Normal Helium has 2 protons and 2 neutrons in its nucleus, giving it an atomic weight of 4, thus the name Helium4.
Now, if the Helium atom loses a neutron somehow, you get Helium3. This happens once in a while in very energetic nuclear reactors. About one in every ten thousand helium atoms ejected from the sun comes out missing a neutron, thus naturally occuring Helium has 1.3 parts in a million of Helium3.
Helium3, lacking a neutron to be optimally stable will attempt to grab one if it can. At high temperatures, the nucleii of He3 and Deuterium will get close enough for that transfer to take place.
Deuterium and Helium-3 Nuclear Fusion
D + He3 --> p + He4 + 18.4 MeV
This is a nuclear fusion reaction. The Deuterium and Helium3 atoms come together to give off a proton and Helium4. The products weigh less than the initial components; the missing mass is converted to energy. 1 kg of Helium3 burned with 0.67 kg of deuterium gives us about 19 megawatt-years of energy output.
A reactor built to use the D-He3 reaction would be inherently safe. Helium4 is not dangerous, and the proton is highly reactive and will not remain in a free state for very long. Unlike other reactions, there are no neutron emmissions. The worst-case failure scenario would not result in any civilian fatalities or significant exposures to radiation.
Outward Bound on Helium3
With this kind of power at our fingertips, the reaction mass vs. ship's velocity ratio drops to numbers that make interplanetary flight quite reasonable (and speedy!). But how would it work exactly?
The ship would have two tanks of fuel. One of Deuterium and another of Helium3. The two gasses would be introduced into a reaction chamber in the rear of the craft, where the gasses would be heated to fusion temperatures with the use of a pul se laser (and perhaps a fission based catalyst).
As the reaction progressed and the gasses expanded, they would be ejected through an opening in the reaction chamber. This opening would direct the ejecta, allowing for an optimal use of the generated thrust.
Additional thrust could be obtained by introducing a non-reactive reaction mass, such as an inert gas or captured interstellar hydrogen. This injected mass would also become plasma and expand, forcing its way out of the reaction chamber and giving additional thrust.

many thanks for this. it seems as though Helium 3 is an incredibly powerful source...i found this article in the sun of all papers!

"Russia aims to race the US back to the Moon and to start mining for a precious fuel. It plans to put its first men on the lunar surface within nine years, beating AMericas 2018 target. US astronauts last went there in 1972.
Russia intends to set up a permanent base and dig for helium 3 an energy resource rare on earth but abundant on the moon with estimates of up to 500million tons. Space freighters will ship it to earth to run thermo-nuclear power station. Just 25 tons a shuttle load could power the USA for a year. Gerald Kulcinski of the university of wisconsin said "helium 3 fusion energy may be the key to future space exploration and settlement""

I guess its a case of finding the right companies who will supply this source of energy and whether its economically viable!

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