Plutonium (pronounced
/plu?'to?ni?m/, symbol
Pu, atomic number 94) is a rare
radioactive,
metallic chemical element. The most significant
isotope of plutonium is
239Pu, with a
half-life of 24,100 years; this isotope is
fissile and is used in most modern
nuclear weapons.
Plutonium-239 can be synthesized from natural
uranium.
The most stable isotope is 244Pu, with a half-life of approximately 80 million years, long enough to be found in extremely small quantities in nature, making 244Pu the most nucleon-rich atom that naturally occurs in the Earth's crust, albeit in small traces.[1]
Pu-239 is suitable for use in nuclear weapons and nuclear reactors. Pu-238 is suitable for use in radioisotope thermoelectric generators.
Plutonium is a silvery radioactive actinide metal that, with thorium and uranium, is one of the few fissile elements; those that have isotopes capable of breaking apart into lighter elements through nuclear fission in relatively easy ways. In both film and television shows, such as The Simpsons, plutonium is often illustrated as a bright green luminous substance similar to Uranium glass, or sometimes in liquid form. However, metallic plutonium normally resembles lead, and only certain isotopes of it glow, due to a significant amount of it decaying and emitting blackbody radiation. Even then the glow is bright orange rather than green.
