| Thermonuclear Weapons | ||
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A detonation of a thermonuclear bomb. Picture courtesy of http://www.co-ra.com A thermonuclear or a hydrogen bomb uses a normal nuclear bomb as a trigger, to create enough heat to start a fusion reaction. A fusion reaction uses deuterium and tritium as fuel, and because of this the fuel is plentiful. The first hydrogen bomb to be detonated was detonated on a small island in the Pacific Ocean in 1952. The new bomb was 500 times more powerful than the Hiroshima bomb; it produced a 5km wide fireball that obliterated the entire island leaving behind an underwater crater 60m deep and 1.5km across! At the center of a thermonuclear bomb, there is a normal atomic bomb, surrounding that is a layer of lithium deuteride (a compound of lithium and deuterium). Around it is a tamper, a thick outer layer of fissionable material, that holds the contents together in order to obtain a larger explosion. Neutrons from the atomic bomb exploding cause the lithium to fission into helium, tritium and energy. The atomic explosion also supplies the temperatures needed for the subsequent fusion of deuterium with tritium, and tritium with tritium (5,000,000°K and 40,000,000°K, respectively). Enough neutrons are produced in the fusion reactions to produce further fission in the core and to initiate fission in the tamper. Although one event must follow the other for the weapon to work, they happen so rapidly that they appear to be a single event, an explosion of unearthly magnitude. Since the fusion reaction produces mostly neutrons and very little that is radioactive, the concept of a “clean bomb” or a bomb that has a small atomic trigger, a less fissionable tamper, and therefore producing a smaller fallout, is a possibility for a weapon. The neutron bomb, which would have a minimum trigger and a non-fissionable tamper, is an extension of the “clean bomb” concept. There would be blast effects and a hail of lethal neutrons, but almost no radioactive fallout; this theoretically would cause minimal damage to buildings and equipment, while killing most living things. The theorized cobalt bomb, is a radioactive “dirty bomb” having a cobalt tamper. Instead of generating additional explosive force from fission of uranium, the cobalt is transmuted into cobalt-60, which has a half-life of 5 1/4 years and produces energetic (and thus penetrating) gamma rays. The half-life of cobalt-60 is just long enough so the airborne particles will settle and coat the earth’s surface before significant decay has occurred, thus making it impractical to hide in shelters. “The ‘Little Boy” bomb that destroyed Hiroshima was a fission atomic bomb. One Peacekeeper ICBM of today, for example, contains 10, W87 thermonuclear warheads, equaling over 100,000 times the power of the original bomb. |
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