Nuclear fission animation. Nuclear fission is the source of the energy released in a nuclear bomb or nuclear reactor. - HD Stock-Video

It occurs when an atom of uranium-235 (red and yellow) absorbs a neutron (yellow), causing it to split into two smaller nuclei (krypton-92 and barium-141), gamma rays (flashes) and three free neutrons. This releases a large amount of energy, and the neutrons can then split other uranium nuclei. In a reactor, materials that absorb free neutrons are used to control the rate of the reaction. In a nuclear bomb, there is a runaway chain reaction that releases an immense amount of energy