The atomic bombs had been created through the Manhattan Project. They created two bombs. The first bomb was called Little Boy, and was to be dropped on Hiroshima, and the second bomb was called Fat Man, and was to be dropped on Nagasaki. Nuclear bombs are much more powerful than other bombs. Six days after the explosion over Nagasaki, and after the Soviet invasion of Manchukuo, Japan surrendered to the Allied Powers on August 15. Japan signed the surrender paper on September 2. This officially ended the Pacific War and World War II.