Nuclear Reactors for Space

Radioisotope power sources have been an important source of energy in space since 1961. Fission power sources have been used mainly by Russia, but new and more powerful designs are under development in the USA.

Nuclear-Powered Ships

Over 160 ships are powered by more than 200 small nuclear reactors. Most are submarines, but they range from icebreakers to aircraft carriers. In future, constraints on fossil fuel use in transport may bring marine nuclear propulsion into more widespread use.