The Manhattan Project was a top-secret US government program that developed the world’s first atomic weapons. Officially formed in 1942, the project’s explicit goal was to develop an atomic weapon before Nazi Germany.
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The bombing of Hiroshima and Nagasaki were inarguably devastating, but almost six decades later there is still widespread disagreement regarding how many people were killed by the atomic bombs—both on the day of the bombings and in the months and years that followed. Estimates differ by as many as 100,000 people. This article explores the issue, as well as why people may favor one number over another.
Nuclear fission is what makes nuclear energy—and nuclear weapons—possible. But what exactly is nuclear fission? This short video, from the PBS program NOVA, uses mousetraps, ping pong balls, and a patient nuclear scientist to help viewers understand what fission is, how scientists do it, and why it’s so powerful.
The brutal 82-day Battle of Okinawa—where US forces suffered nearly 50,000 casualties and Japanese military and civilians lost over 200,000 lives—clinched the grim reality that a full invasion of Japan would be even bloodier. This stark lesson directly shaped American decisions to deploy atomic weapons, aiming to avoid a potentially catastrophic ground war on the Japanese mainland.
Building an atomic bomb is incredibly complex. Creating the first atomic bombs required the joint effort of some of the world’s most celebrated physicists and thousands of workers scattered across the US. This detailed article from the Encyclopedia of the History of Science describes these challenges in great detail, and how those working on the Manhattan Project addressed those challenges.
J. Robert Oppenheimer, the director at the Los Alamos Laboratory of the Manhattan Project in New Mexico during the 1940s, credited with developing and testing the world's first atomic bomb, spoke to a CBS interviewer in 1965. This eight-minute video shows Oppenheimer's ambivalence about his role in the destruction of Hiroshima and Nagasaki, and the changes nuclear weapons brought about in the world in the 20 years since they had first been used.
In 1961, the Soviet Union dropped what is thought to be the most powerful nuclear weapon ever actually tested. Named AN602, it is more commonly known as the Tsar Bomba. Russia released footage of the blast in 2020, and the video—shared here by the Reuters news agency—underscores the destructive power of nuclear warfare.
No one person is more closely identified with the Manhattan Project than Robert Oppenheimer. This feature details Oppenheimer’s upbringing, the characteristics that made him indispensable to the Manhattan Project, and how his later years were marked by a conflict between pride in the project and a deep-seated hatred of weapons of mass destruction.
The writer fought in World War II and witnessed the firebombing of Dresden, which he recounted in 1969's satirical "Slaughterhouse Five." Six years earlier, though, he wrote about the bombing of Hiroshima in "Cat's Cradle," channeling some of the horror he witnessed in Dresden to write about the dropping of the atomic bomb.
The National WWII Museum’s “To the Best of My Ability” podcast series delves into how Presidents Franklin D. Roosevelt and Harry S. Truman steered the US through World War Two.
On August 6, 1945, a bomber named the Enola Gay dropped an atomic bomb on Hiroshima. It was the first time an atomic bomb had been used in combat. The bomb, called Little Boy, destroyed five square miles of the city and killed tens of thousands. This article details the events and offers perspective from both the pilot of the Enola Gay and a Japanese minister who survived the bombing.
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