Pathfinder

An artist's concept of a space based vehicle using the Propulsive Small Expendable Deployer System (ProSEDS) to generate its thrust to maintain orbit without using a propellant. ProSEDS will obtain thrust as the current flowing through the tether experiences a drag force due to interaction with the Earth's magnetic field. Drag force is coupled mechanically to the stage via the tether, thus lowering the stage's orbital altitude.