On January 24, 1978, a bright, fiery object crossed the sky over the sparsely populated north of Canada. A powerful explosion followed, and witnesses first assumed that a giant meteorite had struck the ground. Investigators later found metallic fragments scattered around the area. Tests on that material detected radiation, which did not fit the theory of an ordinary meteorite. The evidence instead pointed to the crash of a Soviet satellite carrying a nuclear reactor. The account says the reactor aboard the lost spacecraft made the debris hazardous. The incident became notable because the wreckage was initially mistaken for a natural object rather than the remains of a Soviet nuclear-powered satellite.