Plutonium-239 found inside a broken, rusty safe has been shown to be of historic significance: dating from December 1944 it is the very first weapons-grade plutonium refined at the site ...

Seaborg submitted a paper on their discovery to the journal Physical Review in March 1941, but the paper was removed when it was discovered that an isotope of plutonium, Pu-239, may be used to ...

have become the number one concern of workers at the plant. Plutonium-239, the isotope found in the spent MOX fuel, is much more radioactive than the depleted Uranium-238 in the fuel. Plutonium ...

A Massachusetts man accused of selling plutonium ... through which he marketed and sold radioactive materials, including Plutonium-239 allegedly derived from Cold War-era Soviet smoke detectors ...

Left to its own devices, plutonium decays slowly. The real danger comes when humans interfere. Related: What is the Standard Model? An isotope of plutonium named plutonium-239 is fissile ...

Plutonium-239 is the last nucleus with such a quantum spin left to analyse – partly because plutonium has a number of complex magnetic properties that interfere with the measurements.

The half-life of plutonium-239 is 24,000 years, so if it escaped in smoke from a burning reactor and contaminated soil downwind, it would remain hazardous for tens of thousands of years.

Like U-235, the only naturally fissile isotope, Pu-239 and Pu-241 can be readily split to release about 1-2 million times as much energy as burning similar mass of petroleum. Plutonium's real ...