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The probability of space rubble hitting a person is so small that Lloyds of London considers the odds impossible to calculate. Nevertheless, in 1969 a Japanese freighter in the Sea of Japan was struck by wreckage from a Soviet spacecraft. There were reports from Tokyo that five crewmen were seriously injured. They remain the first and only victims of debris from space.
Perhaps the two most celebrated space-trash incidents took place within the past decade. In 1978 Cosmos 954, a five-ton, nuclear-powered Soviet ocean-surveillance satellite, lost altitude; its remains were scattered over hundreds of square miles of subArctic Canada. The following year, NASA'S 77½-ton Skylab broadcast a trail of wreckage across the Indian Ocean and Australian outback. There had been plenty of advance warning that both craft were in trouble, although scientists could not accurately predict where the debris would land.
More serious than the danger to earth is the threat that space debris poses for satellites and other extraterrestrial conveyances. Shuttle 10 returned to earth last February with a pea-size pit in its windshield. NASA has reserved judgment on the cause, but the dent is probably the result of a micrometeorite strike or a fragment of titanium, beryllium or other space-age material striking the craft.
Orbital space has become so crowded in recent years that launched objects frequently pass within 30 miles of one another. NASA intentionally sent off the most recent shuttle at the earliest possible opportunity in April to make sure that the orbiter would fly no closer than 130 miles to Soviet space station Salyut 7. Said a Kennedy Space Center launch technician: "We have had a kind of unwritten agreement with the Soviets to keep our launch vehicles at least 200 kilometers away from their birds."
Despite measures taken to prevent accidents, two U.S. satellites collided in 1965, scattering a cloud of debris in their wake. Evidence suggests that in 1981 Cosmos 1275, a Soviet navigation satellite, was blown into 135 fragments by an errant piece of space debris. In 1975 a metallic U.S. communications balloon deflated after colliding with a junk fragment.
The success of last month's Solar Max satellite repair mission provided a potential solution to some of the orbital traffic headaches. NASA has suggested that on future missions space-walking astronauts may be able to collect some of the space junk with grapples, rope it in line like freight cars, attach the tethers to rockets and propel the material either into the earth's oceans or to special garbage dumps in space. One possible site: the moon. "Who knows?" says one NASA official. "A junkyard out there could be a good place for us to find spare parts one day."
—By Jamie Murphy. Reported by Jerry Hamtifin/Washington
—Even that count is incomplete, since NORAD did not include objects that have escaped the earth's gravitational clutches, such as the abandoned Viking lander on Mars or Pioneer 10, which last June flew beyond the outermost planet of the solar system.