CryoSat-1

CryoSat-1, also known as just CryoSat, was a European Space Agency satellite. It was to have been operated as part of the CryoSat programme to study the Earth's polar ice caps. The CryoSat spacecraft was intended to operate in low Earth orbit for three years. It had a mass of 750 kilograms (1,650 lb) Its primary instrument, Synthetic Aperture Interferometric Radar Altimeter (SIRAL), was to have used radar altimeter to determine and monitor the spacecraft's altitude in order to measure the elevation of the ice, and for radar imaging of the ice caps. A second instrument, DORIS, was to have been used to calculate precisely the spacecraft's orbit. It also carried an array of retroreflectors which would have allowed measurements to be made from the ground to verify the orbital data provided by DORIS.