1942 ⟶ First Nuclear Chain Reaction Achieved

Below the bleachers of Stagg Field at the University of Chic...
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Year
1933
1939
1942

⚛️ Szilard Conceptualizes Nuclear Chain Reaction

Leo Szilard conceives the idea of the nuclear chain reaction.⟶
Szilard Conceptualizes Nuclear Chain Reaction (1933)
ScienceNuclear PhysicsLeo SzilardNuclear Chain ReactionResearchTechnologyAtomic BombWeaponsWorld War II

⚛️ Uranium Atom Split at Columbia University

A uranium atom is split for the first time at Columbia University in the United States.⟶
Uranium Atom Split at Columbia University (1939)
USSciencePhysicsNuclear FissionTechnologyAtomic BombColumbia University

✉️ Einstein-Szilard Letter Sent to Roosevelt

The Einstein–Szilard letter is sent to President Roosevelt. Written by Leo Szilard and signed by Albert Einstein, it warned of the danger that Germany might develop atomic bombs. This letter prompted action by Roosevelt and eventually resulted in the Manhattan Project.⟶
Einstein-Szilard Letter Sent to Roosevelt (1939)
USEinsteinSzilardRooseveltAtomic BombManhattan ProjectScienceGermanyNuclearWar

☢️ First Nuclear Chain Reaction Achieved

Below the bleachers of Stagg Field at the University of Chicago, a team led by Enrico Fermi initiates the first nuclear chain reaction. A coded message, "The Italian navigator has landed in the new world" is sent to President Roosevelt.⟶
First Nuclear Chain Reaction Achieved (1942)
USNuclearChain ReactionFermiManhattan ProjectScienceTechnologyWorld War IIAtomic BombChicago

⚛️ Manhattan Project Officially Begins

Manhattan Engineering District is formally created, full-effort development of the atomic bomb and production of nuclear fuels is begun.⟶
Manhattan Project Officially Begins (1942)
Manhattan ProjectAtomic BombNuclear WeaponsUnited StatesWorld War IIScienceTechnologyWarfare