nuclear weapon: Quick Facts

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Last updated

Oct. 9, 2026

Facts

Also Known As	atomic weapon • thermonuclear weapon

Photos and Videos

U.S. hydrogen bomb test in the Marshall Islands

World War II: total destruction of Hiroshima, Japan

M65 atomic cannon

Nuclear submarine

Diagram showing the sequence of uranium nucleus fission after being struck by a neutron: the nucleus absorbs the neutron, deforms, splits into fragments, releases more neutrons and gamma rays, and emits beta particles as the fragments decay. Labels identify neutrons, protons, beta particles, and gamma rays, with accompanying explanatory text.

Diagram showing three nuclear weapon designs: a gun-assembly fission bomb with uranium-235 and a conventional explosive, an implosion fission bomb with a plutonium-239 core surrounded by explosive lenses, and a boosted-fission bomb with a plutonium core, uranium tamper, and fusion fuel, all labeled with their main components inside cutaway metal casings.

Nuclear fission and fusion

Diagram showing the Teller-Ulam two-stage thermonuclear bomb design, with four labeled stages: a chemical explosion in the primary fission core, X-ray transfer and compression, ignition of a secondary fusion stage, and fusion fuel detonation. Key components such as the fission fuel, uranium tamper, and polystyrene foam are illustrated and labeled.

View footage of the first test of a hydrogen bomb carried out by the United States in the Marshall Islands

Watch U.S. B-29 Superfortress Enola Gay decimate Hiroshima with a nuclear bomb in the Pacific War

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Topics

doomsday machine nuclear electromagnetic pulse tactical nuclear weapons intermediate-range nuclear weapons Atomic Annie atomic bomb thermonuclear bomb neutron bomb gun-assembly fission bomb Teller-Ulam configuration mine grenade ammunition Greek fire napalm nuclear strategy nuclear football

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Key People

Atal Bihari Vajpayee

Atal Bihari Vajpayee

prime minister of India

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Yuly Borisovich Khariton

Russian physicist

Lord Noel-Baker.

Philip John Noel-Baker, Baron Noel-Baker

British statesman

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David Lange

prime minister of New Zealand

Alva Myrdal.

Alva Reimer Myrdal

Swedish diplomat

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Raja Ramanna

Indian nuclear physicist

Bertrand Russell

Bertrand Russell

British logician and philosopher

Teller, Edward

Edward Teller

Hungarian-born American physicist

Abdul Qadeer Khan

Abdul Qadeer Khan

Pakistani scientist

Freeman Dyson

Freeman Dyson

American physicist

A.P.J. Abdul Kalam

A.P.J. Abdul Kalam

president of India