Surveillance Constellations of Low Altitude Small Satellites with Electric Propulsion

Small spacecraft may carry out surveillance of crisis areas in an effective way when deployed in constellations. In order to limit cost, small spacecraft shall operate at low orbital altitude, so as to use small and relatively unexpensive optical payloads. We show that extended operation in low LEO is made possible by the use of electric propulsion for atmospheric drag compensation. Mission performance is discussed with reference to utilization for the surveillance of a Mediterranean/Middle East region with an extended mission target lifetime of up to 8 years. The constellation design and the overall spacecraft arrangement are presented, as well as the electric propulsion subsystem, based on the HT100 Hall thruster by Alta