Question: has there ever been a nuclear bomb set off

Answer: Yes, So far, two nuclear weapons have been used in the course of warfare, both by the United States near the end of World War II. On August 6, 1945, a uranium gun-type device (code name ``Little Boy'') was detonated over the Japanese city of Hiroshima. Three days later, on August 9, a plutonium implosion-type device (code name ``Fat Man'') was detonated over the Japanese city of Nagasaki. These two bombings resulted in the deaths of approximately 120,000 people.