Before A-bombings
Why were the A-bombs dropped? 

 

Development of A-bombs 

In 1939, a full-scale war broke out in Europe and in 1941, a war began between Japan and the United States. 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. 

 

Japan selected as A-bomb target 

In September 1944, before the completion of the atomic bombs, the President of the United States of America and the Prime Minister of the United Kingdom held talks and agreed that the bombs should be dropped on Japan. On August 2, following a nuclear test in July 1945, the United States of America ultimately decided upon sites to drop the bombs with Hiroshima as the first target, Kokura as the second, and Nagasaki as the third. 

 

A-bomb drop on Nagasaki 

The United States dropped the first atomic bomb on Hiroshima, on August 6, 1945. The second bomb was initially scheduled to be dropped on Kokura on August 9, three days after the first bombing. However, visibility was poor when the U.S. B-29 bomber carrying the A-bomb arrived over Kokura, so it headed to Nagasaki and dropped the bomb from a height of 9,600 meters. At 11:02 a.m., the A-bomb exploded approximately 500 meters above Matsuyama-machi.