Sailing satellites out of orbit

SEN reveals the poetic way we’re planning to keep tomorrow’s satellites from turning into space junk:

In low orbits, there is still sufficient atmosphere to generate the needed drag thanks to the large sail size. Even with the sail, it could take up to 25 years for the satellite to reenter and disintegrate, but to deorbit in the same time frame using traditional thrusters would require ten times the equivalent mass in propellant. For satellites in higher orbits beyond the atmosphere, the sail could potentially use solar radiation pressure to descend with the help of an attitude control system ‘solar sailing’.

At launch, the Gossamer Deorbit Sail is extremely compact, occupying 15x15x25 cm and weighing only 2 kg. It would expand in minutes to 5×5 m, enough to bring down a satellite of up to 700 kg. A frame of extremely lightweight carbon-fibre booms supports a sail of aluminised Kapton only a few thousandths of a millimetre thick, a fraction of the diameter of human hair.

The team hopes to see it validated in orbit using a demonstration satellite by the end of 2014 on a piggy-back launch opportunity.