This section provides an overview of the history of the Manhattan Project, the key organizations involved, the science behind the bomb, and more.
Norris Bradbury standing next to the Gadget Device. Each of the 32 detonators (circles with two wires) attached to the Fireset (box) using two bridgewires.

Electronics and Detonators

Manhattan Project scientists and engineers in Los Alamos, NM designed and developed a number of innovations in the field of electronics.
Clinch River

Environmental Consequences

Both the Oak Ridge and Hanford sites were chosen for their isolation and access to hydropower from surrounding river systems.
A World War II poster


Espionage was one of General Groves' main concerns during the Manhattan Project.
The Dampierre Nuclear Power Plant in northern France

French Nuclear Program

France became the fourth country to possess nuclear weapons after its first test in 1960. While development was slowed by the impact of World War II, the achievements of early French research were critical for nuclear development worldwide.
Haigerloch Nuclear Pile

German Atomic Bomb Project

“I don't believe a word of the whole thing,” declared Werner Heisenberg, the scientific head of the German nuclear program, after hearing the news that the United States had dropped an atomic bomb on Hiroshima.

Positron emitter detector (circa 1962) used to detect brain tumors.

Health Physics & Nuclear Medicine After the Manhattan Project

Today, millions of nuclear medicine procedures are performed in the United States every year, where the legacy of the Manhattan Project lives on in the treatment and visualization of disease.
Applications of x-rays in medicine from 1910

Health Physics & Nuclear Medicine Before the Manhattan Project

Shortly after its discovery, radiation became an invaluable part of medicine. However, people soon realized that radiation could also be extremely dangerous.
Oak Ridge National Laboratory workers turning in their pocket dosimeters (circa 1950)

Health Physics & Nuclear Medicine During the Manhattan Project

The Manhattan Project produced a large number of radioactive substances, and as a result scientists intensified research into the overlap of nuclear science and medicine.
A historical sample of "heavy water" produced by Norsk Hydro. By Alchemist-hp (talk) (www.pse-mendelejew.de) (Own work) [FAL], via Wikimedia Commons

Heavy Water Reactors

As scientists decided which materials they would use to build the early nuclear reactors, some staked their country’s nuclear programs on small amounts of a substance practically indistinguishable from water.