CryoSat ( later because of subsequent CryoSat -2 called CryoSat -1 ) was a research satellite, which should capture the cryosphere measure the Earth and, in particular, the volume of ice in the Arctic and Antarctic. After the start of the satellite orbit is not reached but due to a faulty control algorithm and crashed into the Arctic Ocean. CryoSat was the first of the Earth Explorer Missions within the Living Planet Programme of the European Space Agency ( ESA). From this mission, the science hoped for additional findings on the change in the climate of the earth. The aim was to measure the exact surface heights of the land ice masses in Greenland and Antarctica. In addition, from space the thickness of floating sea ice should be recorded for the first time. The plan was a service life of at least three years.

The total cost of the mission, including the launch vehicle, operating costs and data analysis were estimated by ESA with 136 million euros, of which 70 million euros for the satellite alone.


Of the 650 -kg and 4.60 × 2.34 × 2.20 meter satellite was built by EADS Astrium. Its main payload consisted of the radar altimeter SIRAL ( SAR / Interferometric Radar Altimeter ) with two antennas of 1.14 × 1.25 meters size which operate with 25 watts of power at a frequency of 13.575 GHz. SIRAL should achieve a vertical resolution of 1 to 3 cm and a horizontal resolution of about 300 meters at its measurements. In this case, the radio signals to be sent with an interval of 50 microseconds, and detected again. Between three different operating modes are provided for different application areas (land and sea ice ). These are conventional pulse - limited operation, synthetic aperture mode and Zwei-Kanal-SAR/interferometrischer operation, in which the SAR mode, a better discrimination of ice and water and the interferometric operation enables a more accurate determination of the slope of the ice surface and its height. In addition, the radio receiver was DORIS (Doppler Orbit and Radio Positioning Integration by Satellite ) and a small laser retroreflector for exact positioning of the satellite on board. For communication an X- band antenna for scientific data ( on-board memory capacity of solid state recorder 256 Gbits ) and an S-band helical antenna for telemetry and control were found. To navigation and position control are three star tracker cameras, magnetometers and magnetic controls and cold-gas attitude control thrusters of 10 milli Newton thrust. The power supply should be done by at the satellite surface fixedly mounted gallium arsenide solar cells with 800 watts and lithium ion batteries with 60 Ah. CryoSat should work in a 720 km high polar orbit with an inclination of 92 °, optimized for the observation of the polar regions. The European Space Operations Centre of ESA in Darmstadt should ensure the operation of the satellite.

Mission History

The satellite was carried out on 8 October 2005 at 15:02 UTC clock from Plesetsk with a Russian Rockot KM launcher. After initially perfect start, the Briz- KM upper stage of the rocket did not separate from the second stage, so that the head portion of the rocket came down together with the satellite in the Arctic Ocean ( Lincolnsee between Greenland and the North Pole ). This was caused by a program error. The control provided for to switch off the second step after the third step had ignited during the third stage should fire only after the second not fired. Consequently, both stages were coupled to the burning of the second stage. The course deviation caused thereby led to the rejected take-offs and loss of the satellite.

CryoSat -2

After the failure of the Member States decided ESA end of February 2006 to carry out a replacement mission because of the importance of the project. The original target launch date for this was in October 2009, was carried out by various delays the start only on April 8, 2010. 's Mission was initially for three years, but was extended to seven.