Over Christmas vacation in 1938, physicists Lise Meitner and Otto Frisch received puzzling scientific news in a private letter from nuclear chemist Otto Hahn. When bombarding uranium with neutrons, ...

Three colorless solutions are combined into a large beaker and the mixture becomes amber, then blue-black, and then colorless again. This sequence of color changes will repeat with a period of ...

The Atomic Age began at 3:25 p.m. on Dec. 2, 1942—quietly, in secrecy, on a squash court under the west stands of old Stagg Field at the University of Chicago. Today, Henry Moore’s “Nuclear Energy” ...