Jason-CS A, B (Sentinel 6A, 6B / Sentinel 6 Michael Freilich)

Jason-CS [Airbus]

The Jason-CS (Jason Continuity of Service) or Sentinel 6 radar altimeter mission is a continuation of the existing partnership for Jason-3 between the US (NOAA and NASA) and Europe (EUMETSAT, ESA, CNES) and industry.

Jason-CS, as the reference mission of the Ocean Surface Topography constellation, should ensure the same (or better) level of performance as earlier Jason series. The spacecraft will be based on a platform derived from CryoSat-2, but adjusted to the specific requirements of the Jason-CS mission and specific orbit. The orbit will remain the same as the earlier Jason orbit - non-sun-synchronous, 1336 km, 66° inclination.

The responsibilities in the Jason-CS program are:

• EUMETSAT is leading the system definition and is responsible for the Jason-CS ground segment development; operations preparation and operations of both satellites, and will co-fund the recurrent Jason-CS-B satellite, together with the European Commission (EC).
• ESA is responsible for the development of the first Jason-CS-A satellite; the prototype processors; delivery of the LEOP services, and the procurement of the recurrent satellite on behalf of EUMETSAT and the EC.
• The EC co-funds the recurrent Jason-CS satellite with EUMETSAT and funds the operations of Jason-3 and both Jason-CS satellites, including the LEOP service for the second Jason-CS-B satellite.
• NOAA provides the launch services for both Jason-CS satellite; US payload instruments and ground segment support, and will contribute to the operations.

The payload considered as the baseline for the satellite, Phase B2, is composed of the following instruments:

• a radar altimeter, developed by ESA, based on the heritage from the Sentinel-3 SARL instrument, but with a design adopted to allow the interleaved mode combining the SAR and the LRM modes;
• AMR-C Microwave radiometer, provided by NOAA;
• GNSS Precise Orbit Determination (POD) Receiver, developed by ESA and derived from the GNSS Receiver on Sentinel-3;
• the same DORIS Receiver as on Jason-3 and Sentinel-3;
• the same Laser Reflector Array as on Jason-3, provided by NOAA;
• radio-occultation instrument based on a Tri-G receiver, provided by NOAA.

Airbus has won in May 2015 a contract to build the first Jason-CS satellite. It will be launched in November 2020 on a Falcon-9 v1.2 (Block 5) from Vandenberg.