Hiroshima Atomic Bombing
The United States dropped the first atomic bomb used in warfare on Hiroshima
August 06, 1945
8:15 AM, August 6, 1945
At 8:15 in the morning, a US B-29 bomber called Enola Gay dropped a uranium bomb nicknamed "Little Boy" over the Japanese city of Hiroshima. The bomb detonated at about 580 meters above the city center. The explosion released energy equivalent to 15,000 tons of TNT. Within seconds, the temperature at the blast's center reached 3,000–4,000°C — hotter than the surface of the Sun. An estimated 70,000 to 80,000 people died instantly. By the end of 1945, the death toll reached 90,000 to 140,000.
The Decision
President Harry Truman authorized the bombing to avoid a land invasion of Japan, which military planners estimated would kill hundreds of thousands of American soldiers and millions of Japanese civilians. Japan had shown no willingness to surrender despite devastating conventional bombing of its cities. Three days after Hiroshima, a second bomb — "Fat Man," made of plutonium — was dropped on Nagasaki, killing another 40,000 people instantly. Japan surrendered six days later.
The Nuclear Age
Hiroshima and Nagasaki remain the only uses of nuclear weapons in warfare. The bombings ushered in the nuclear age — an era defined by the knowledge that humanity now possessed weapons capable of destroying civilization. The Trinity test had demonstrated the technology was possible; Hiroshima showed the world what it meant in human terms. August 6 is now Hiroshima Peace Memorial Day, observed worldwide.