This image shows the mushroom cloud produced by the atomic bomb dropped on Nagasaki Japan on august, 9th, 1945. It was one of two dropped on Japanese cities by the allies. This action brought the world into the atomic age. It is a powerful image because it documents the event which catalysed the surrender of Japan and the end of world war two. At the same time it changed the course of the world forever and ushered in the cold war.