Heavy water (deuterium oxide, D2O) is a form of water that contains a higher than normal concentration of the isotope deuterium, rather than the common hydrogen-1 isotope. It is used in certain types of nuclear reactors, known as heavy-water reactors, as a neutron moderator to slow down neutrons and increase the probability of nuclear fission.[^1] By 1953, Israeli researchers at the [[Weizmann Institute of Science]] had pioneered a new process for creating heavy water. This development was crucial for [[Israel]]'s nuclear ambitions, as [[David Ben-Gurion]] had repeatedly stated that [[Israel]] would build its own atomic reactor utilizing locally manufactured heavy water.[^1] ### Footnotes [^1]: Hersh, Seymour M. *The Samson Option: Israel's Nuclear Arsenal and American Foreign Policy*. Random House, 1991. Chapter 2.