Final Activity Report Summary - PEGASES (Plasma Propulsion with Electronegative Gases)
The development of new space propulsion systems is required for both deep space and near earth exploration, as conventional thrusters are not yet satisfactory. The PEGASES project aimed to revolutionise the current space technology by developing a new concept for electric propulsion. This concept, patented by Ecole Polytechnique in early 2007, exploited ion-ion plasma, i.e. an electron-free plasma, from which both positively and negatively charged ions were accelerated to provide thrust.
The PEGASES thruster used electronegative gases as propellant so that the generated plasma consisted of both positively and negatively charged ions in addition to electrons. A magnetic field was applied to filter away electrons, allowing for plasma stratification with an electron-free ion-ion plasma region in the extraction zone. Ions with opposite charges from this electron-free region were accelerated separately in space or in time by biased grids. This concept provided two main advantages over existing plasma propulsion systems:
1. there was no need for an additional electron neutralisation system and
2. the possible damage from charged particles outside of the thruster body was limited because positive and negative ions recombined very fast and quickly formed a neutral beam downstream of the thruster.
During the 24-month intra-European fellowship the PEGASES project concept was developed from an innovative idea to a concrete prototype that was installed in a ground-based vacuum facility. The concept was studied by experiments, simulation and theories and the preliminary results demonstrated a promising future for this new concept. The host institution recruited the fellow as a full time researcher on a permanent basis to ensure the continuation and future success of this project. The team had, by the time of the project completion, an industrial contract with EADS Astrium in France for the development of a portable prototype and was in negotiations with the European Space Agency (ESA) for advanced tests of the thruster that were anticipated to take place during 2010 and 2011.
The PEGASES thruster used electronegative gases as propellant so that the generated plasma consisted of both positively and negatively charged ions in addition to electrons. A magnetic field was applied to filter away electrons, allowing for plasma stratification with an electron-free ion-ion plasma region in the extraction zone. Ions with opposite charges from this electron-free region were accelerated separately in space or in time by biased grids. This concept provided two main advantages over existing plasma propulsion systems:
1. there was no need for an additional electron neutralisation system and
2. the possible damage from charged particles outside of the thruster body was limited because positive and negative ions recombined very fast and quickly formed a neutral beam downstream of the thruster.
During the 24-month intra-European fellowship the PEGASES project concept was developed from an innovative idea to a concrete prototype that was installed in a ground-based vacuum facility. The concept was studied by experiments, simulation and theories and the preliminary results demonstrated a promising future for this new concept. The host institution recruited the fellow as a full time researcher on a permanent basis to ensure the continuation and future success of this project. The team had, by the time of the project completion, an industrial contract with EADS Astrium in France for the development of a portable prototype and was in negotiations with the European Space Agency (ESA) for advanced tests of the thruster that were anticipated to take place during 2010 and 2011.