July 1941 – British MAUD Committee Releases ‘Use of Uranium as a Source of Power’ Report by VNEC Staff | Jul 1, 1941 | Timeline
December 14, 1940 – Dr. Glenn T. Seaborg, Joseph W. Kennedy, Edwin M. McMillan, and Arthur C. Wahl Produce and Isolate Plutonium by VNEC Staff | Dec 14, 1940 | Timeline
1940s – Uranium is First Enriched in the United States as Part of The Manhattan Project by VNEC Staff | Jan 1, 1940 | Timeline
1940 – Soviet physicists Georgy Flyorov and Konstantin Petrzhak Demonstrate Spontaneous Fission by VNEC Staff | Jan 1, 1940 | Timeline
August 29, 1939 – Bohr and Wheeler Publish an Analysis of the Fission Process by VNEC Staff | Aug 29, 1939 | Timeline
May 1939 – Francis Perrin Introduces the Concept of the Critical Mass of Uranium Required to Produce a Self-Sustaining Release of Energy by VNEC Staff | May 1, 1939 | Timeline