CNES projects library

January 6, 2017

Jason 3

Jason-3 is the third in the French-American line of Jason satellites. It ensures the continuity of ocean level data from its orbital viewpoint, 1,336 km above Earth.

For the world’s oceanographers, the Jason series of altimetry satellites is a vital resource. TOPEX/Poseidon, launched in 1992, Jason-1 in 2001, and then Jason-2 in 2008 have revealed that the global sea level is rising at an average rate of 3 mm per year. They have also helped scientists to better understand the vast system of deep and surface ocean currents. Today, they have become a benchmark for other altimetry satellites like SARAL, CryoSat, HY-2A and SWOT, and their operational applications are burgeoning.

Jason-3 ensures vital continuity of the ocean data record in the current context of global warming until at least 2020, while also developing operational services. Like its predecessors, it operates in a high-inclination 1,336-km orbit from which it covers 95% of the globe’s ice-free oceans every 10 days. Its instruments are installed on a Proteus spacecraft bus supplied by CNES. In 2020 and 2026, two new Jason satellites—respectively Jason-CS-A/Sentinel-6A and Jason-CS-B/Sentinel-6B—will join it in the same orbit.