NUCLEAR RESEARCH TIME LINE
1896
French physicist Antoine Henri Becquerel discovers natural radioactivity.
1905
German-born scientist Albert Einstein publishes theory that matter and energy are equal.
1911
British physicist Ernest Rutherford announces his discovery of the nucleus of the atom.
1913
German Hans Geiger invents a radiation detector that bears his name.
1930
Princeton University researcher Robert van de Graaff builds an early particle accelerator, the Van de Graaff generator.
American physicist Ernest Lawrence invents the cyclotron, which uses a magnetic field to accelerate atomic particles.
1934
Italian-born US physicist Enrico Fermi proposes use of neutrons to split atoms.
1938
German chemists Otto Hahn and Fritz Strassmann achieve first fission of uranium.
1939
Einstein writes a letter to President Franklin D. Roosevelt, warning of the military uses of atomic energy.
1940
US scientists receive $6,000 for atomic research.
1942
The Manhattan Engineer District of the Army Corps of Engineers (The Manhattan Project) is organized to produce an atomic bomb.
Fermi and colleagues achieve first artificially created chain reaction at the University of Chicago on Dec. 2.
1943
A laboratory directed by J. Robert Oppenheimer is created on an isolated mesa at Los Alamos, N.M.
1944
Two methods of uranium enrichment, necessary to produce fissionable material, are developed: gas diffusion and an electromagnetic means.
1945
Funding for the Manhattan Project has grown to $2 billion.
The first atomic bomb is exploded near Alamogordo, N.M., in a secret predawn test on July 16.
