Finnish invention reduces space debris

The Finnish Meteorological Institute has developed a plasma brake capable of reducing the amount of debris left in space. Using the plasma brake, small satellites can be returned to the atmosphere after their service life, thus preventing the accumulation of space debris.

– In principle, the deorbiting device could be, for example, a braking rocket, but especially for small satellites, the inclusion of a rocket engine would increase total costs considerably. The plasma brake developed at the Finnish Meteorological Institute is a negatively charged tether made of a thin metal wire. Interacting with the ionosphere, the tether reduces the satellite's speed so that its orbit falls gradually, says Pekka Janhunen, Research Manager at the Finnish Meteorological Institute.

Depending on the size of the satellite, the plasma brake is estimated to weigh only a few hundred grams. The device is about ten times more efficient than the previously known electrodynamic tether. The plasma brake tether is so thin that it poses no risk to other satellites.

The plasma brake was invented at the Finnish Meteorological Institute by the same group that previously invented the electric solar wind sail, a revolutionary propulsion method for planetary probes that is now being developed in Finland and elsewhere in Europe. Both inventions will be tested on the Estonian ESTCube-1 nanosatellite to be launched in 2012.

www.fmi.fi