Charles Q. Choi, Space.com (March 17, 2011)
"Lasers on the ground could be used to nudge debris in orbit, which could help move dangerous space junk away from satellites and spacecraft, scientists working with NASA suggest.
"Space debris might not sound like much of a threat until one realizes that in low-Earth orbit, 'these objects are typically going at about 7.5 kilometers per second, or almost 17,000 miles per hour,' said physicist James Mason, a NASA contract scientist at the Universities Space Research Association. 'To put this in perspective, a 1-ounce piece of debris traveling at this velocity has about the same kinetic energy as a 2-ton car traveling at 60 miles per hour.'
"The problem that debris poses gets worse when collisions spawn even more debris, eventually cluttering space with high-speed shrapnel, a scenario nicknamed 'Kessler syndrome' after NASA scientist Donald Kessler, who predicted it in 1978.
" 'The February 2009 collision between an active Iridium sat-phone satellite and a defunct Russian Cosmos weather satellite was the first example of an active satellite being catastrophically destroyed in an accidental collision,' Mason said. 'Collisions like this were predicted by Kessler in 1978, and he predicted that if the number of debris in certain orbits got high enough then there would be a cascading series of collisions that might eventually render whole orbits unusable.'..."
Information Age services like GPS, television, telecommunications, and weather forecasting depend at least partly on satellites orbiting Earth. The growing collection of junk in orbit is a very practical concern. In the Lemming's opinion, of course.
Using lasers to vaporize bits of space junk, producing thrust/recoil that would nudge them toward Earth - where they'd burn out like meteors - is one way of disposing of the debris. Another would be to rendezvous with each individual piece and do about the same thing. Since there are "Hundreds of thousands of pieces of space junk," (Space.com (December 23, 2011)) it'd probably be cheaper and quicker to use lasers.
The good news is that we've got technology that could - with a bit of development and testing - start nudging orbiting debris out of the sky.
The bad news is that the technology would be seen as a weapon by some folks. And that opens at least one can of legal and diplomatic worms.
Somewhat-related posts:
- "Last Flights of the First Space Freighters, New Construction at Spaceports"
(September 23, 2010) - "European Space Agency Inheriting Huge Satellite, and Trouble to Match"
(July 27, 2010) - "Space Tourism and Virgin Galactic: Another Step"
(July 17, 2010) - "Bigelow Aerospace: Space to Rent or Lease, in Orbit"
(January 20, 2010) - "Over Four Dozen Space Agencies (and Growing?)"
(February 28, 2010)
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