After 50 years of searching, physicists have spotted the fingerprint of radioactive plutonium, revealing the secrets of this complex molecule behind nuclear weapons. The researchers found the ...

Opinions differ on whether the half ton of weapons-grade plutonium secretly shipped by the U.S. government to the Nevada National Security Site could impact residents’ health and the environment.

(CNN) — Idaho State University has been fined after it lost track of a small amount of plutonium 239, a substance used to make nuclear weapons. University Officials say the sample, missing since 2003, ...

It’s widely known that a smoke detector is a good ionizing radiation source, as they contain a small amount of americium-241, a side product of nuclear reactors. But what about other sources? [Carl ...

Devoted fans can wait hours on the red carpet to get their favourite movie star’s autograph, but that’s nothing compared to acquiring the signature of plutonium-239. After 50 years of trying, ...

The clean-up of a decommissioned US nuclear weapons plant has unearthed one of the oldest known samples of man-made plutonium. Workers found roughly half a gram of weapons-grade plutonium-239 (Pu-239) ...

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, or anywhere ...

Today in jeepers: There's a speck of weapons-grade plutonium missing in Idaho. According to a Nuclear Regulatory Commission (NRC) statement, 1 gram (0.04 ounces) of plutonium-239 — about the weight of ...