What happened
Kosmos 954 was a Soviet naval reconnaissance satellite from the RORSAT program, powered by a small nuclear reactor. Launched in September 1977, it soon began losing altitude uncontrollably, and the system that was supposed to separate the reactor at the end of the mission and boost it into a higher orbit failed. On January 24, 1978, the satellite reentered the atmosphere over northern Canada, and radioactive debris fell along a strip stretching from Great Slave Lake, near the settlement of Fort Resolution, toward Baker Lake. Canada and the United States conducted a months-long operation, “Morning Light,” recovering larger fragments and thousands of tiny radioactive particles. Canada billed the USSR for the cost of the operation, and Moscow ultimately paid 3 million Canadian dollars.
Witnesses
U.S. and Canadian air defense services, which tracked the satellite; the debris was found by participants in Operation “Morning Light.”
Explanations and hypotheses
The event is fully explained: a failure of the reactor separation system caused the satellite and its nuclear fuel to burn up in the atmosphere over inhabited territory. It was the first case in which one state billed another for damages under the Outer Space Treaty. The case prompted the UN to develop principles on nuclear power sources in outer space.
Explained The phenomenon has a widely accepted, down-to-earth explanation.
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