Tuesday, April 22, 2014

Space Junk Cleaning Satellites, Anyone?

Given that space junk has now grown in number to threaten “commercial” activities in space, can a space junk clearing satellites provide a viable solution?

By: Ringo Bones

Since the launching of Sputnik and other related space faring satellites in the late 1950s, there are now about 12,000 objects in orbit that can be tracked by radar. Unfortunately objects 1 centimeter in diameter or smaller that can potentially damage commercial and manned spacecraft entering low earth orbit that can’t be tracked by ground based radar are believed to number around 750,000. Given these number of orbiting space debris or orbital space debris, it is now a statistical possibility that the International Space Station could experience a serious hull breaching collision by orbiting space junks once every 3 years. Would space junk capturing satellites be a viable solution of making the orbital space around our planet safer for both multi-million dollar commercial and scientific satellites – not to mention manned spacecraft?

The Clean Space family of satellites one prototype called Clean Space One had been developed and functional prototypes now exist. Designed by Herbert Shea and co designer Volter Grass of the Swiss Space Center uses an artificial muscle equipped robotic arm to grab non functioning satellites or satellites that have ended their service lives and drag them back down to lower orbit in order to burn up in the earth’s upper atmosphere. The main disadvantage of these satellites is that they are not reusable and they can “dispose” or clean up” only one satellite at a time – a single clean up mission could end up costing tens to hundreds of millions of dollars. Though improved prototypes based on the artificial muscle equipped robotic arm concept could someday clean up tiny debris with diameters of 1 centimeter or smaller that can be reusable by sending the recovered space junk to a manned mother-ship, as opposed to a burn-up reentry. Sadly, Ronald Reagan era "Star Wars" or Strategic Defense Initiative type laser based systems are still not powerful and reliable enough to clean up orbital space debris.