At 11:02 AM on August 9th, 1945, an atomic bomb was dropped on the city of Nagasaki. The bomb exploded approximately 500 meters above the city with the force of over 21 kilotons of TNT. All the buildings within a 2.5 km radius of the hypocenter were instantly vaporized. By the year's end, approximately 1/3 of the city's population of 240,000 was dead with another 1/3 severely injured.