Topex-Poseidon satellite orbiting the Earth,artwork. This satellite,launched in 1992,was a joint mission between NASA and the CNES (the French space agency). It was designed to map ocean surface topography,the first satellite to do so extensively. This allowed global monitoring of sea level,tides,ocean currents and oscillations,ocean circulation,and climate change. The measurements were made with two radar altimeters,named Topex (topography experiment) and Poseidon. The satellite was shut down in 2006 following a malfunction. The successor mission was Jason-1,which was launched in 2001 |