Example image of eyePlorer eyePlorer map for 'Gun-type fission weapon': Critical mass Nuclear fission Nuclear weapon Nuclear weapon design Artillery Uranium Hiroshima Little Boy Mark 11 nuclear bomb Mark 8 nuclear bomb Mark 10 nuclear bomb Uranium-235 Cordite Nuclear chain reaction Shake (time) Spontaneous fission U-238 Thin Man nuclear bomb Nuclear reactor technology Plutonium-239 Plutonium-240 Fat Man Criticality accident Louis Slotin Nuclear proliferation Nuclear terrorism Nuclear artillery United States United Kingdom South Africa Neutron moderator Seawater 1953 May 25 Nevada Test Site W9 (nuclear warhead) Operation Upshot-Knothole TNT equivalent Nuclear weapon yield M65 Atomic Cannon W19 (nuclear artillery shell) W33 (nuclear weapon) Advena Upshot-Knothole Grable South Africa and weapons of mass destruction Silverplate Atomic bombings of Hiroshima and Nagasaki Trinity (nuclear test) Timeline of Nuclear Weapons Development Underground nuclear testing