Credit: Universidad Carlos III de Madrid
How to propel a spacecraft without propellant? Use electrodynamic tethers. These are long, strong conductors connecting two spacecraft. When direct current is applied to the tether, the tether exerts a force on the spacecraft, causing it to either accelerate or brake.
Such tethers might be used to perform fuel-free orbital maneuvers, or deorbit satellites at the end of their working lifetime to prevent buildup of orbital debris.
Universidad Carlos III de Madrid in Spain has proposed an improved tether design incorporating thin film solar cells to harvest added power for the tether plasma circuit, …