If the ISS-near miss last week was any indication, space debris is becoming more of a hazard to orbital navigation. If it isn’t the Chinese blowing up satellites, its the Americans blowing up satellites, or the Russians crashing into satellite*s (“crashing” for the cynically-minded).
The latter event — where a Russian satellite took out an Iridium satellite — is what supposedly caused the debris that made for a dramatic Friday morning for twitterers and ISS crew alike. Especially the crew, of course.
So, this article in Russia Today, says that the Japanese are developing microsatellites to grab debris, presumably, some of the medium-sized pieces, and fall back to earth. The tether idea sounds neat (but the headline sounds vaguely inappropriate).
Japan’s space agency (JAXA) is planning to use microsatellites to clear orbits from space junk. The robotic cleaner grabs debris with a robotic arm and then lunges down to force the dangerous pieces back into atmosphere.
The 140-kilogram device uses electrodynamics tethers to drag down the debris. The tethers are conductive wires with lengths of up to several kilometres, which can be used to generate propulsion.
The Japanese cleaner approaches debris, attaches itself to it with a robotic arm, and then moves to a lower orbit, unwinding the tether from a reel. An electric current is generated in the tether, which interacts with Earth’s magnetic field to create drag, which slows down the debris making it re-enter the atmosphere and subsequently burn up. The satellite, of course, is destroyed in the process as well.
*OK, how cool is it that Iridium had backups parked in orbit already?