Nuclear fusion is when atoms are forced together to form a new atom.  This is the form of power that is used in the Sun.  In the Sun, Duratanium is fused with Helium 3.  The result is an unfathomable amount of energy, a proton, and an atom of Helium.  The problem with fusion is it takes place at over 10 million degrees Kelvin.  Scientists are working on Cold Fusion, fusion at "low" temperatures - low being between 100,000 degrees Celsius and 1,000,000 degrees Celsius.

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