An Electrodynamic Tether System for Propulsion and Power Generation in a Jovian Mission

The paper concerns an innovative propulsive/power system exploiting the magnetic field and the charged atmosphere present on some planets of our solar system. In fact a conductive tether moving in the above mentioned environment is able to provide a low thrust for orbital control and/or power generation for on-board systems. This solution is considered particularly promising for the exploration of outer planets where the low solar luminosity makes the use of solar panels unsuitable. On the other end the use of radioactive thermoelectric generators (RTG) might be ruled out on future missions due to the finite risk of releasing plutonium into the terrestrial environment. The main objective of the present paper is the assessment of the feasibility and applicability of an electrodynamic tether system to missions devoted to the exploration of the Jovian system. Among the outer planets, at the present stage of knowledge, Jupiter is by far the most promising target for the proposed system application. In fact, it has a large and energetic magnetosphere ideally suited for electrodynamic tether operations and due to its rapid rotation, its magnetic field sweeps the tether rather than being swept by it (as in the Earth case). The net effect will be the increase of spacecraft momentum, thus allowing the raise of its orbit, and/or on-board power generation, without any expenditure of propellants.