Hiroshima

1945 · réf. 12596 — 1945. World War IIAtomic Bomb Van Kirk Theodore J. "Dutch". Single blueprint copy inscribed and signed dated "6 Aug 1945." Single blueprint sheet. Annotated blueprint of "Little Boy" the uranium-235 atomic bomb detonated over Hiroshima on August 6 1945 inscribed and explained by Theodore Van Kirk navigator of the B-29 Enola Gay during the first wartime use of a nuclear weapon. Developed under the direction of the Manhattan Project the bomb marked a decisive technological and geopolitical rupture at the close of World War II inaugurating the nuclear age and reshaping global military doctrine. Approximately 70000 people were killed as a direct result of the blast with comparable numbers injured rendering the event one of the most consequential military actions of the twentieth century. Black-and-white blueprint copy approximately 18 x 24 inches illustrating the internal configuration of "Little Boy" employing the gun-type assembly method in which a sub-critical uranium-235 projectile was fired into a hollow uranium-235 target to achieve supercritical mass and initiate a nuclear chain reaction. Van Kirk has added detailed manuscript notations in pencil and ink identifying principal components including the "Neutron Source" "Steel Tamper" "Gunpowder" "Explosion Device" "Highly Sensitive Radio Antennae" "Uranium 235 'Bullet' Fired into Target to Create a Critical Mass" and "Uranium 235 Hollowed out Target." Along the margin in black ink he writes: "This is a blue print of our Hiroshima Atomic bomb 'Little Boy.' It was the only uranium bomb made. The bomb was designed as a gun type bomb with a bullet of U-235 fired into a U-235 target to create a critical mass." Signed below in blue ink: "Theodore J 'Dutch' Van Kirk Navigator - Enola Gay 6 Aug 1945." The design of "Little Boy" was finalized by early 1945 and reflected a conservative engineering approach intended to ensure detonation reliability despite the unprecedented nature of atomic warfare. As a navigational officer on the mission Van Kirk occupied a critical operational role in delivering the weapon to its target and his explanatory annotations reveal how participants later articulated the bomb's mechanics and singular status as the only uranium-based device used in combat. Minor edge wear and light handling marks; blueprint lines sharp and legible; manuscript annotations and signature clear and strong. Overall very good to near fine condition. unknown