More than 60 years ago, Japan, Germany and Italy fought a war with the United States, the United Kingdom, the Soviet Union and other countries. In August 1942 the United States, fearing that Germany might be developing a new type of bomb using atomic energy (the vast energy produced during nuclear fission), launched the Manhattan Project to develop an atomic bomb (A-bomb). Three years later, the atomic bomb was created.

In an attempt to end the war, the United States was developing atomic bombs originally planned for use against Germany. However, before the bombs’ full development Germany had surrendered, in May 1945. The plan was therefore changed, to use the new weapons on Japan. The United States held discussions to select the A-bombing target cities in Japan, and finally decided to drop A-bombs on Hiroshima, Kokura and Nagasaki.

After successfully carrying out an A-bomb test in July 1945, the United States dropped the first atomic bomb on Hiroshima, on August 6 of the same year.

The second atomic bomb was initially scheduled to be dropped on Kokura on August 9, three days after the first bombing. However, when the U.S. B-29 bomber carrying the A-bomb arrived over Kokura, the city was blanketed with clouds. Unable to drop the device on the primary target, the B-29 made its way to its secondary target, Nagasaki. At 11:02a.m., the B-29 dropped its deadly cargo over Nagasaki from a height of 9,600 meters above Matsuyama-machi; the A-bomb exploded approximately 500 meters above the ground.