By Peter Weiss
At U.S. ports and border crossings, agents are increasingly using X-ray surveillance of shipping containers and trucks to foil attempts to smuggle nuclear weapons or radioactive materials into the country. A new study indicates that radiation from the heavens may provide a way to detect such threatening cargoes without requiring potentially dangerous X-ray sources.
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Konstantin N. Borozdin of Los Alamos (N.M.) National Laboratory and his coworkers have demonstrated in a laboratory experiment that they can use the relentless rain of cosmic rays to detect chunks of heavy metal. The researchers report their findings in the March 20 Nature.