A DANGEROUS COLLECTION of man-made space debris has reportedly accumulated in an orbiting band 1,000 kilometres above the Earth.
The debris, which include discarded rocket boosters and defunct satellites, currently pose a serious threat to operational surveillance, weather and telecom satellites. Recent simulations conducted by NASA suggest that the odds of potential space collisions have increased exponentially, as even objects the size of a grain of sand can impact with the power of a bowling ball moving at 100 mph.
 Indeed, the first incident between two large satellites has already occurred. In February 2009, a defunct Russian military orbiter collided with a live American commercial satellite. Wayward space junk also forced the crew of the International Space Station to take refuge in their escape ship as discarded materials passed their fragile facility.
To address the problem, NASA researchers have proposed the creation of 1,000 kilometer long (600 mile) tethers to lasso discarded objects and drag them closer to the atmosphere where they would be destroyed by friction. However, two Stanford University researchers have instead suggested that countries simply comply with existing NASA regulations that stipulate the removal of objects within 25 years of their original launch date.
According to Professor Lawrence Wein and Andrew Bradley, strict adherence to the rules could help significantly reduce the chances of satellite collisions.
"Spacecraft are supposed to have enough 'gas' in their tanks to propel them downward toward the atmosphere when their life cycle is concluded. But international compliance, while perhaps greater than 50 per cent, is not extremely high," Professor Wein told The News. "Our analysis predicts that, despite a slow increase in the rate of collisions over the next millennium, the risk of a catastrophic collision to an operational spacecraft can be kept below 1 chance out of 1,000 for all future time if we focus on very high compliance of deorbiting spacecraft from low Earth orbit after their useful life. If we can achieve high compliance, there should not be a need to develop space tethers to retrieve large objects from space."
Wein explained that the space pollution was a prime example of environmental economics, with the region representing a "renewable resource."
"Compared to the length of time man has been contributing to ocean pollution, space is just beginning to suffer from man's encroachment. Taking action now will protect communication satellites today as well as protect a resource," said Wein. The researcher also suggested that governments level launch fees and penalise those who ignore their floating trash.
"The political and economic issues associated with the establishment of such fees are fairly daunting. But if we could get high compliance this problem could stay under control," added Wein.
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