Little Boy

Featured Artifact

Displayed at the Museum is an exact replica of Little Boy, the bomb that destroyed Hiroshima, Japan, on August 6, 1945, during World War II.

Little Boy was a relatively simple enriched-uranium weapon designed and built at Los Alamos. Little Boy consisted of two pieces of uranium separated in the barrel of a gun. It exploded when the projectile was fired at the the target piece, creating a total mass that was supercritical, or able to sustain a nuclear chain reaction resulting in an explosion.

Weight - 9,700 pounds
Length - 120 inches
Diameter - 29 inches
Yield -15 Kt, equivalent to 15,000 tons of TNT
Fissile material - Uranium-235

Little Boy bomb