Also known as SensorSat, the Operationally Responsive Space 5 (ORS-5) will perform surveillance on geostationary (GEO) satellites. The craft will provide a stopgap for the existing space based surveillance system (SBSS), since full replacements are not expected until after 2020. With a mass of approximately 100kg the solar powered craft will operate in low earth orbit at an altitude of 600km.