Differences Between Fusion & Fission

Fission and fusion are nuclear processes by which atoms are altered to create energy. Fission is the division of one atom into two atoms, and fusion is the combination process that joins two lighter atoms to create one larger atom. The processes are opposing and are therefore different in several ways.

Amount of Energy Released and By-products

Fusion produces little radioactive particles unless a fission "trigger" is present and used as a catalyst in the process, which can create radioactive particles after fusion is completed. Fission always creates radioactive substances as its by-products, which are highly radioactive for hundreds of years following the reaction. Compared to the average chemical reaction, fission releases a million times as much energy. However, nuclear fusion produces three to four times the energy of a fission reaction.

Conditions Required

Unlike fission, fusion occurs in nature, as observed in stars. To create fission, you must achieve critical mass of the substance used and access high-speed neutrons to allow for the atoms to separate, which requires very little energy. Very high temperatures and increased density are required for a fusion reaction. Because the electromagnetic repulsion properties of the protons must be overcome, extreme amounts of energy must be harnessed to produce a fusion reaction.

Energy Plants

Fission is considered an alternative energy source because it produces no air pollution. Environmentalists, however, express concerns over the radioactive leftover substances from the reaction. The possibility of fusion energy plants is being explored because fusion creates a rapidly decaying radioactive material and only produces helium, considered a harmless gas.

Military Bombs

Atomic bombs, or A-bombs, are powerful because of the fission reactions that occur within them. These destructive weapons contain enriched uranium or plutonium that is forced into critical mass and leads to an explosion. One megaton atomic bomb can level everything within a 1.7 mile radius. Even more powerful, fusion bombs, or hydrogen bombs, combine fission and fusion to create a massive fusion nuclear reaction, which expands the devastation eightyfold beyond the atom bomb's reach.