The European Aeronautic Defence and Space Company (or EADS) is working on attaching "sails" to satellites so that the orbiting spacecraft could passively drag themselves back to Earth when they're not wanted anymore.

The system is called IDEAS, standing for the Innovative DEorbiting Aerobrake System. The plan right now is to deploy a series of booms that hold gossamer sails, which would increase the drag acting on the satellite and accelerate the decay of its orbit. While satellites normally stay in orbit anywhere from 50 to 100 years, IDEAS-equipped spacecraft would return in less that 25 years.

EADS is developing IDEAS for a French satellite called Microscope, which will complete its mission — testing "the Equivalence Principle with an accuracy of one hundred times better than the one obtained with experiments realized on Earth" — within the span of a year. As Microscope won't be equipped with any thrusters of its own, the sails will help it leave orbit so that it will make room for future spacecraft and avoid potential collisions.

EADS is also looking into configuring IDEAS so that it could be fitted onto space junk already in orbit, to help bring it down sooner. So, really, in 25 years or so we're all going to have to start wearing hard hats.

EADS, via BBC News