The process of nuclear fission was discovered in 1939 by German chemists Otto Hahn and Fritz Strassmann, and Lise Meitner, a physicist from Austria.
They knew about the work of Niels Bohr and Ernest Rutherford and the structure of atoms. Hahn and Meitner experimented with bombarding atoms of uranium, a radioactive substance, with neutrons (small particles found in the nucleus, or center, of an atom).
The process they discovered was nuclear fission. During this process, an atom’s nucleus splits into tinier particles. Small particles called neutrons and photons are produced, and so is a huge amount of energy.
Scientists soon realized that nuclear fission could create energy for nuclear power — but it could also power nuclear weapons. In fact, nuclear fission was the energy behind the nuclear, or atomic, bomb that ended World War II.
Today, nuclear fission makes up about 17 percent of the world’s power supply. That will increase as more nuclear plants come into use.
A nuclear reactor plant can produce power for 20 years without refueling. But nuclear power can also result in disasters such as the nuclear accident in Chernobyl, Ukraine.