The most optimistic U.S. intelligence estimates suggested that the Soviet Union would not be able to produce an atomic bomb before 1953, and the United Kingdom figured it would take at least another year. Yet on August 29, 1949, RDS-1 showed the world that the Soviet Union had become a nuclear power. Nicknamed “Joe-1” after Stalin, the bomb was almost a clone of Fat Man, thanks in no small part to extensive espionage on Western territory and the work of some very intelligent people on the other side of the Iron Curtain.
The birth of the atomic age
On August 6 and 9, 1945, Hiroshima and Nagasaki were blown away. The birth of the “Atomic Age” was confirmed by the deaths of hundreds of thousands of people. Less than a month later, Japanese authorities signed the Instrument of Surrender. World War II had come to an end. The United States had broken the will of a military force willing to sacrifice every last available man with pure nuclear fire. And the Soviet Union was paying close attention.
Of course, the two countries were allies at the time, but Stalin had already made his decision: the Soviet Union had to redouble its efforts and produce a similar device within half a decade or less. Technically, the Soviet nuclear program began during the war, in 1942. Early that year, nuclear physicist Georgy Flyorov noticed that the Allied powers had stopped publishing studies related to atomic advances, virtually confirming suspicions of a secret program. In two letters sent to Stalin (the second backed by physicist Konstantin Petrzhak), Flyorov recommended the immediate creation of a uranium bomb.
Nobody knows for sure whether Stalin received those letters, but from that point onward, Russian physicists were pulled from their military postings to work on the project. Igor Kurchatov was named head of Laboratory No. 2 near Moscow (founded in February 1943). Despite progress, the Soviet Union reached the end of World War II empty-handed, facing uncertainty and difficulties in developing a uranium variant. After Hiroshima and Nagasaki, the Politburo took control of the atomic program, and from April 1946 all efforts were channeled into a plutonium design.
https://old.neoteo.com/m65-atomic-annie-el-supercanon-que-disparaba-bombas-nucleares/Why it looked like Fat Man
Which brings us to RDS-1. Its similarities to Fat Man were no coincidence: the entire Soviet espionage network in the West was strikingly successful at leaking technical details and designs derived from the Manhattan Project and other sources. Theodore Hall, Harry Gold, Klaus Fuchs (probably the most important asset for Russian intelligence), David Greenglass, Julius and Ethel Rosenberg, and at least half a dozen more spies were all involved.
RDS-1, “Device 501,” “First Lightning,” or simply “Joe-1,” was an implosion bomb with a solid plutonium core that produced a yield of 22 kilotons when it detonated (Fat Man reached 21 kilotons). To gauge the bomb’s destructive power, workers at the Semipalatinsk Test Site (now Kazakhstan) built brick and wooden houses, a bridge, and even a mock subway. Military equipment with reinforced armor, grounded aircraft, and 1,500 animals were also included.
The secret is out
The Soviet Union thought it had kept the detonation relatively secret, but the United States had Boeing B-29 units fitted with special filters that could detect radioactive material. On September 3, 1949, a B-29 flying from Misawa base (Japan) to Eielson base (Alaska) registered a positive detection. Russia had the bomb. The American nuclear monopoly was dead. President Truman shared the news of the RDS-1 explosion with the public twenty days later, while ordering his officials to accelerate work on the hydrogen bomb. The result? The Teller-Ulam design, and the detonation of Ivy Mike.
