Orbiting junk, from old satellites to space gloves, has scientists worried for spacecraft - and engineers working on ways to clean it up.
If you want to get rid of an old fridge or an obsolete TV, you could call for curbside pickup. But an obsolete satellite? Or a spent rocket?
Increasingly, the space about Earth is getting cluttered with such junk. And it's not just messy, it's dangerous. Full-size rocket bodies can destroy. Even smaller pieces - such as a 1965 space glove that zipped around for a month at 17,000 miles per hour - amount to more than a smack in the face. They can puncture space suits and cripple satellites.
Fortunately, the aerospace community is giving the problem increasing attention. Engineers are considering everything from techniques for rendering derelict satellites and boosters less harmful, to an international "space traffic control" system, to Earth-based lasers that can zap the stuff.
But the problem is expected to get worse as governments and companies prepare to triple the satellite population over the next two decades and send more people into space.
"If we don't change our ways, this could become a serious problem," says William Ailor, who heads the Center for Orbital Reentry Debris Studies at the Aerospace Corporation in El Segundo, Calif.
As if to underscore the concern over space-junk hazards, over the past year the United States government has adopted spacecraft and mission-design rules to minimize the contribution its spacecraft make to the space-debris problem. Now, the International Bureau of the US Federal Communications Commission (FCC) is putting the finishing touches on proposed debris-reduction rules that would govern commercial satellites as well. The drafts could hit the commissioners' in-boxes as early as December, notes Karl Kensinger, associate chief of the bureau's satellite division.
Ever since Sputnik, humans have lobbed more than 20,000 metric tons of hardware into orbit. In addition, Dr. Ailor notes that the number of operating satellites is expected to grow from 700 today to as many as 3,000 in 2020.
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