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Hunter-Killer Satellite to Take Out Space Junk

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Researchers at The Australian National University and Tohoku University in Japan have proposed a new way to deal with space junk – a “hunter-killer satellite”.

In a paper published in Scientific Reports (, the researchers propose that a satellite powered by superheated gas could shoot a beam of hot plasma at space junk from the opposite end of the satellite. This would allow the satellite to either push the space junk down into a lower orbit so it eventually decays, or push it up to get it out of the way of other objects.

“Our tests show you can push plasma out one end of a satellite to thrust it towards the junk, and then push it out the other end to send that junk in the right direction,” said Prof Rod Boswell of the ANU Research School of Physics and Engineering. “If you can throw the gas out as a plasma, or charged gas, you can throw it out very quickly and make much better use of the fuel. You throw out less of it, because it’s thrown out very fast.”

A piece of space junk will naturally decay within around 2 years if it’s less than 500 km from the Earth’s surface, because the atmosphere is still dense enough to cause friction, which causes the junk to gradually get slower and lower. Above 500 km, however, Boswell says: “It’s going to take a long time to come...

The full text of this article can be purchased from Informit.