Atomic bomb

Nuclear weapon of the "Little Boy" type, the kind detonated over Hiroshima, Japan, in World War II. The bomb is 28 inches in diameter and 120 inches long. The first nuclear weapon ever detonated, it weighed about 9,000 pounds and had a yield equivalent to approximately 20,000 tons of high explosive.

Area of devastation by the atomic bombing of Hiroshima, Japan.

Atomic Bomb Explosion, test at Alamogordo, New Mexico.

President Harry S. Truman (left) greeting Prime Minister Clement Attlee of England upon his arrival at the White House. Mr. Attlee is in the U.S. to discuss the problem of atomic energy with the President.

Portrait of Dr. Leonard Schultz, Washington, D. C. (of the Smithsonian Institution), who is among the Washington men appointed to study the effect of the atom bomb tests held at Bikini Atoll. From: Beth Gore.

Portrait photo of physicist Robert F. Bacher, named by President Harry S. Truman on October 28th to serve on the new Atomic Energy Commission. From: Beth Gore.

Detonation of an atom bomb during the experimental tests at the Eniwetok Proving Grounds.

Fireball rises from an atom bomb explosion during the tests at Eniwetok casting its reflection on the water.

The fireball of an atom bomb explosion emerges through cloud formations, forming into the already familiar mushroom, during the experimental tests at Eniwetok.

Fireball and shockwave of an atomic bomb explosion, during the tests held at Eniwetok.