Junk hunting satellite uses plasma thrust to de-orbit debris

Known as the ‘Sheppard’ system, it uses a bi-directional argon plasma thruster to both position itself in proximity to space junk and send the debris into a lower orbit to burn up. Research published in Scientific Reports shows how the team was able to control the plasma ejections precisely in both directions so that force can be imparted to the space junk while the satellite itself remains stationary.

"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 from 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."