Once the war was over, scientists could concentrate on other uses for this new source of tremendous amounts of energy.
Nuclear power plants were built to use fission to produce electricity.
There are now over 400 nuclear power plants in the world. France and Sweden produce nearly half their electricity with nuclear power.
There are two drawbacks, however, to nuclear power. There is always the possibility of an accident.
In 1986, a Russian nuclear reactor exploded, killing 19 people immediately and contaminating a huge area of Russia with harmful radioactivity.
Nuclear power plants also produce nuclear waste, which needs to be buried deep underground.
The waste remains radioactive for 13 million years.
Huge amounts of energy are also produced by nuclear fusion, when the nuclei of two small masses combine into one large mass.
The Sun produces its energy by nuclear fusion.
