Parametric Study of HEMP-Thruster, Downscaling to N Thrust Levels IEPC-2013-269 Presented at the 33 rd International Electric Propulsion Conference, The George Washington University, Washington, D.C., USA October 6–10, 2013 Andreas Keller, ∗ Astrium GmbH - Satellites, Friedrichshafen, Germany Justus-Liebig-University Gießen, I. Physikalisches Institut, Germany Peter K¨ ohler, Justus-Liebig-University Gießen, I. Physikalisches Institut, Germany Franz Georg Hey, Astrium GmbH - Satellites, Friedrichshafen, Germany Technische Universit¨at Dresden, Germany Marcel Berger, Astrium GmbH - Space Transportation, Bremen, Germany Claus Braxmaier, University of Bremen, ZARM Center of Applied Space Technology and Microgravity DLR German Aerospace Center, Institute of Space Systems, Bremen Davar Feili, University of Southampton, Faculty of Engineering and the Environment, United Kingdom Dennis Weise, Ulrich Johann Astrium GmbH - Satellites, Friedrichshafen, Germany Abstract: Many on-going ESA’s science and Earth Observation missions are based on fine attitude control and formation flying. All these missions apply strong requirements on propulsion system which should provide low thrust and high precision thrust vectors in up to 16 directions. Also as the most of these missions have a platform with small solar cell arrays, the power consumption of the propulsion system should be very low. The idea of using a small HEMP thruster for such missions is very attractive due its relatively low subsystem complexity and low system mass. So the ability of down-scaling a HEMP-T to the N range is investigated experimentally. A measurement campaign study- ing systematically the influence of the geometrical dimensions of main thruster parts on operation, beam profile and ion acceleration is presented. Additionally the anode material was varied which shows an impact to ion acceleration distribution. The minimum achieved thrust was 50 N and 70 s by 350 V anode voltage. * Andreas.Keller@exp1.physik.uni-giessen.de 1 The 33 rd International Electric Propulsion Conference, The George Washington University, USA October 6–10, 2013