Before testing the first atomic bomb, some of the scientists working on the Manhattan Project did their best to calculate what might happen. They estimated there was a three percent chance the bomb would set the entire world’s atmosphere on fire, instantly killing us all. They went ahead and tested the bomb.
Facts About the Manhattan Project
It Was Named After an Office in New York
The project was originally designated the “Development of Substitute Materials.” To maintain secrecy, it was renamed the Manhattan Engineer District (and later the Manhattan Project) because its initial headquarters were located at 270 Broadway in Manhattan, New York.
It Was Initiated by a Letter Signed by Albert Einstein
In August 1939, concerned that Nazi Germany might develop nuclear weapons, physicists Leo Szilard and Eugene Wigner drafted a letter to President Franklin D. Roosevelt warning him of the danger. They persuaded Albert Einstein to sign it, which directly led to the U.S. government establishing what would become the Manhattan Project.
It Was Larger and More Expensive Than Most Realize
At its peak, the project employed over 130,000 people and cost roughly $2 billion at the time (equivalent to over $30 billion today). It was one of the largest industrial and secret scientific endeavors in history.
It Spanned Dozens of Sites Across North America
While Los Alamos, New Mexico, hosted the secret laboratory responsible for bomb design, key research and production facilities spanned the continent:
Oak Ridge, Tennessee: Uranium enrichment plants.
Hanford, Washington: Plutonium production reactors.
Chalk River, Ontario: Canadian heavy water research support.
A Secret City Consumed 10% of the Nation’s Electricity
Oak Ridge, Tennessee—built entirely from scratch in secret—became the fifth largest city in the state during the war. Its massive uranium enrichment facilities consumed approximately 10% of all electrical power produced in the United States at the time.
The Silver from Fort Knox
Due to wartime copper shortages, the project borrowed over 14,000 tons of pure silver from the U.S. Treasury to make electrical wiring for electromagnets used in uranium separation. All of the silver was melted down, drawn into wire, used, and eventually returned to the Treasury after the war with virtually none lost.
Soviet Spies Infiltrated the Highest Levels
Despite extreme compartmentalization and security protocols, several scientists and technicians passed critical technical details to the Soviet Union. Key spies included Klaus Fuchs, Theodore Hall, and David Greenglass, which significantly accelerated the USSR’s own atomic bomb development after WWII.
“Calutron Girls” Operated High-Tech Equipment Without Knowing What It Did
Thousands of young women, mostly high school graduates, were hired at Oak Ridge to operate Calutrons (devices used to enrich uranium). They were trained purely to monitor dials and adjust switches, remaining completely unaware of the facility’s purpose until the bombs were dropped in 1945.
The First Bomb Was Named “Gadget”
The world’s first nuclear detonation—the Trinity Test on July 16, 1945, near Alamogordo, New Mexico—used a plutonium implosion device affectionately nicknamed “Gadget.” Scientists were so uncertain of the outcome that Fermi famously took bets on whether it would ignite the Earth’s atmosphere (though calculations proved this impossible).
The Scientists Wore Sunglasses for the First Atomic Blast
During the Trinity Test, observers were instructed to lie face down with their feet toward the blast and cover their eyes. Many scientists, including Richard Feynman, chose to watch through dark welding goggles or behind heavily tinted glass; Feynman famously sat inside a truck windshield, arguing the glass would block the UV radiation.
Speaking of scientists run amok, you might find this interesting: Yelling At Chickens.