Cleaning Up the Final Frontier

If the world needed a reminder of the sheer amount of stuff swirling around the planet, it received a spectacular one in mid-November. The European Space Agencys 1.2-ton GOCE satellite, which had studied the earths gravitational field, ran out of fuel in low orbit, reentered the earths atmosphere, burned up into a fiery mess, and dumped debris across the southern Atlantic just south of the Falkland Islands. The Inter-Agency Space Debris Coordination Committeea global space agency consortium that tracks space junkactivated surveillance facilities around the world to monitor the destruction of the bird.

Since the Soviets kicked off the Space Age by launching Sputnik1 in 1957, mankind has sent more than 7,100 spacecraft of some sort aloft. Along the way, an expanding miasma of refusemalfunctioning satellites, rocket motor effluents, metal fragments, equipment lost on space walks, and even tiny flecks of painthas spread in orbit. Computer simulations by NASA portray what looks like a cloud of fruit flies swarming around an appleonly these fruit flies travel at 17,000miles per hour. And at that speed even a particle can do serious damage to satellites or spacecrafta scenario dramatized in Alfonso Cuarns sci-fi thriller Gravity.

The space refuse problem is most troublesome in low orbits of about 500miles above the earths surface. There are 21,000 pieces of wreckage the size of grapefruit or biggerand that number grows to 500,000 if you include fragments the size of BB pellets and dust specks, according to NASA data. Some of this detritus is burned off during reentry to earth. But depending on the trajectory, other pieces can stay in orbit for decades, even centuries. Former astronaut Michael Bloomfield remembers watching debris burning up in the atmosphere below him during one U.S. shuttle mission. That gets your attention, he says. So did the time a fragment slammed into the window, leaving a pit mark.

Even so, engineers disagree about how urgent the risk really isand whether governments should spend billions on solutions that are years away from being ready. Thats practical, but maybe not the noblest way to look at the problem. The expense must be weighed against some kind of moral pressure to leave at least the final frontier unwrecked, if only to prove we can. That said, removing the refuse may be even more complicated than getting all that junk up there in the first place. Engineering hurdles aside, theres no international consensus or legal framework to organize and pay for a multidecade cleanup effort.

You might call it the tragedy of the space commons, a 21st century twist on American ecologist Garrett Hardins theory, advanced in the late 1960s, that shared resources like grazing lands and fishing zones can be depleted by individuals, acting independently and rationally, to the greater detriment of a larger group.

Coming to an international agreement about global warming has been tough enough. Its hard to imagine a power like Russia or China signing off on a plan by U.S. or European space agencies to operate the kind of orbiting trash collectors backed by some scientists and companies interested in government contracts. The really hard part is trying to convince other countries that your garbage truck in space will be used for the peaceful purposes statedand not to mess with other peoples satellites, says Dave Baiocchi, an engineering professor at the Pardee RAND Graduate School.

There are three broad and evolving strategies to cope with space debris. One solution starts at blastoff: Theres been progress by commercial companies and space agencies to adopt smarter launch and design standards (limiting the use of explosive bolts, for example, normally used to separate rocket stages) to reduce the amount of space debris entering low earth orbits.

Governments are also investing in systems that can locate the junk. Raytheon (RTN) and Lockheed Martin (LMT) are in the hunt for a multibillion-dollar U.S. Air Force contract expected to be announced later this year that will fund a massive radar system to track stuff. Known as the space fence, it will be based in the Pacific or Australia and promises to give the U.S. the ability to identify more and smaller pieces of space debris with much greater accuracy than current systems.

In November the U.S. and Australia signed an agreement to move an advanced Space Surveillance Telescope developed by the Defense Advanced Research Projects Agency from its current mountaintop position in New Mexico to Australia to better find debris in the higher geosynchronous orbits about 22,000 miles above the earths surface.

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Cleaning Up the Final Frontier