Fallout

Residual radioactive material following a nuclear blast

Fallout
Nuclear fallout is residual radioactive material that is created by the reactions producing a nuclear explosion. It is initially present in the radioactive cloud created by the explosion, and "falls out" of the cloud as it is moved by the atmosphere in the minutes, hours, and days after the explosion. The bulk of the radioactivity from nuclear fallout comes from fission products, which are created by the nuclear fission reactions of the nuclear device. https://en.wikipedia.org/wiki/Nuclear_fallout

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