This section provides an overview of the history of the Manhattan Project, the key organizations involved, the science behind the bomb, and more.
Albert Einstein and Leo Szilard working on the famous letter

The Einstein-Szilard Letter - 1939

In 1939, Albert Einstein sent FDR a letter urging the US conduct research into an atomic bomb.
Fat man.

The Franck Report

Soon after the Interim Committee concluded that the atomic bomb should be used as soon as possible against Japan, a group of scientists led by physicist James Franck founded a committee to study the question of the bomb's use.

The Human Computers of Los Alamos

Before computers became the modern electric desktops or laptops of today, “computers” actually referred to the people who did computing or calculations of equations.
The bombing of Hiroshima

The Interim Committee

As the Manhattan Project neared its first atomic test, there was a growing sentiment among project leaders that an advisory committee to make recommendations on nuclear energy should be created.
The Manhattan Project insignia. Image courtesy of Alex Wellerstein.

The Manhattan Project

What was the Manhattan Project?

The Manhattan Project in Popular Culture

Since 1945, the Manhattan Project has frequently appeared in films, fiction, and many other forms of popular culture.

The Navy in the Manhattan Project

While the secrecy of the Manhattan Project meant that the U.S. Army was the only branch officially charged with overseeing it, the Navy would also play a crucial role in the project’s success.

The Radium Girls

The tragic story of the "radium girls" had an important impact on the Manhattan Project.
Julius and Ethel leaving court after being found guilty, 1951.

The Rosenberg Trial

The trial and execution of Julius and Ethel Rosenberg for passing atomic secrets to the Soviet Union remains controversial today.