ScienceApril 1943

The Los Alamos Laboratory

In 1943 a secret laboratory to design the atomic bomb was founded on a remote mesa at Los Alamos, New Mexico. Oppenheimer, its director, gathered leading scientists including Fermi and Bohr.

Oppenheimer chose the New Mexico mesa he had ridden as a youth for the laboratory. Set up in spring 1943 in the buildings of a boys’ school, it drew scientists from America and refugees from Europe with their families; its only address was P.O. Box 1663.

The scientists built two designs at once: a gun that fired one piece of uranium-235 into another (Little Boy), and an implosion bomb that squeezed a plutonium sphere with explosives from all sides (Fat Man). The Nazi bomb programme that had spurred them on was found by the Allies’ Alsos Mission in late 1944 to have made little progress — yet the work went on.

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States and rulers at the time: United States — President Franklin D. Roosevelt
Places: Los Alamos

People

J. Robert Oppenheimer1904 – 1967
key figure · American physicist who directed the Los Alamos laboratory and led the building of the atomic bomb — the "father of the atomic bomb" — and after the war opposed the hydrogen bomb
Leslie Groves1896 – 1970
commander · US Army general who oversaw the building of the Pentagon and from 1942 commanded the whole Manhattan Project
Enrico Fermi1901 – 1954
participant · Italian-born physicist who, after receiving the 1938 Nobel Prize in Physics, emigrated to the US and achieved the first chain reaction with the world’s first reactor in Chicago in 1942

Before and after

Earlier: 1942 Chicago Pile-1 — The First Chain Reaction
Later: 1945 The Trinity Test

Themes that include this event

The Birth of the Atomic Bomb1938 – 1949
From the discovery of fission to the first Soviet bomb — Einstein’s letter, the Manhattan Project, the Trinity test, Hiroshima and Nagasaki, and the dawn of the nuclear age