What is Nuclear Fusion?

Nuclear fusion is a process during which light atoms fuse to form heavier ones. During the fusion of elements with low atomic numbers substantial amounts of energy are released.

In 1939 Hans A. Bethe of Germany was the first to theorize about nuclear fusion. Bethe suggested that much of the energy output of the Sun and other stars results from reactions in which four hydrogen nuclei unite, form one helium nucleus while releasing a large amount of energy.

Later research proved that fusion reactions can indeed occur only at many millions of degrees Kelvin when the electrostatic forces of repulsion that result from the presence of positive electric

charges in both nuclei can be overcome so that the nuclear forces of attraction can perform a fusion. Such high temperatures, however, do only occur in suns or in uncontrolled nuclear chain reactions (atomic bombs).

During the early 1950s American researchers produced the first human made nuclear fusion reaction by infusing a mixture of the heavy hydrogen isotopes deuterium and tritium into the fission reaction of an atomic bomb. Thus they had created the hydrogen bomb an atomic bomb with enhanced destructive potential.

Scientists have sought practical methods to harness the process nuclear fusion. If one could devise a safe and controlled procedure, nuclear fusion would provide a relatively inexpensive alternative energy source for electric-power generation and thereby become an alternative to the world's dwindling supply of natural energy resources. If successful, controlled fusion could also replace nuclear fission as an energy source. Deuterium, the primary fuel for a fusion-power system, is far more abundant and cheaper than any of the materials required for fission reactions, since it can be extracted from ordinary water. Even at the beginning of the 21st century many experts doubt that controlled fusion will be achieved in the near future because of various technical difficulties.