History of the Atomic Bomb By Kieran Cockburn 3R

It took only 8 years from a theory of nuclear fission to dropping two atom bombs 1937Niels Bohr theorizes that nucleus can be split 1941Fermi makes first nuclear pile with partial success 1942 MayVannevar Bush starts atomic bomb project Nov.Los Alamos work starts (Manhattan Project) Dec.Fermi makes first controlled nuclear chain reaction 1945 July 16“Trinity”, first atomic bomb set off in New Mexico Aug 6“Little Boy” dropped on Hiroshima Aug. 9“Fat Man” dropped on Nagasaki

The Manhattan Project was spread over the U.S. B Reactor, Hanford, Washington Fermi’s pile Exterior view of S- 50 thermal diffusion facility

It took only 3 years from the first chain reaction to the Trinity test bomb. “Trinity” 1945 Fermi’s atomic pile 1942

Only two atomic bombs have ever been set off in war. Hiroshima after “Little Boy” “Little Boy” explosion Hiroshima before bombing Nagasaki 2 days beforeNagasaki 3 days after“Fat Man”Nagasaki before bombing

Does the destruction continue? No nuclear bombs were used in the Cold War No nuclear bombs have been dropped since Nagasaki. The only nuclear bombs set off were probably tests. This includes the “hydrogen” or “thermonuclear” weapons.

mb/history.science/ 360a jpg bomb/museum/m2-1e.html m go to “History of the Atom Bomb” then click “chronology” Bibliography