Heavy Water Reactors

As scientists decided which materials they would use to build the early nuclear reactors, some staked their country’s nuclear programs on small amounts of a substance practically indistinguishable from water.

Discovery of Mendelevium

Mendelevium, or element 101, was discovered at the Berkeley Rad Lab in 1955 using advanced techniques and tools.


By 1938, the confused chemistry of uranium became the "topic of the day" at laboratories everywhere.


Plutonium was first produced and isolated on December 14, 1940 at the University of California, Berkeley.