Minimize Overveiw

The SENTINEL-6 mission is intended to be part of the European Commission Copernicus initiative, the overall objective of which is to support Europe's goals regarding sustainable development and global governance of the environment by providing timely, quality data, information, services and knowledge.


The main objective of the SENTINEL-6 mission is to measure sea surface topography with high accuracy and reliability to support ocean forecasting systems, environmental monitoring and climate monitoring. The mission definition is driven by the need for continuity in provision of TOPEX and JASON missions, with improvements in instrument performance and coverage.


The SENTINEL-6 mission will be a multi-agency partnership comprising ESA, EU, EUMETSAT, NASA-JPL, NOAA, and CNES, to deliver operational ocean and land observation services:


ESA provides the majority of funding and development of the SENTINEL-6A satellite, procurement of the SENTINEL-6A and -6B satellites, responsibility for Launch and Early Orbit Phase (LEOP) and Satellite In Orbit Verification (IOV) services. In addition, ESA supports the system IOV commissioning and validation activities, and is jointly responsible for mission performance and developing the radar altimeter prototype processors.


The European Union (EU), through the European Commission (EC), is responsible for funding the operations and participation in funding the SENTINEL-6B satellite.


EUMETSAT is responsible for system coordination, mission management coordination, ground segment and flight operations, contributing funding for the first satellite and participates in funding for the second satellite. It is jointly responsible for mission performance.


NASA-JPL is responsible for the US payload (Microwave Radiometer, Radio-Occultation Receiver, Laser Retro-reflector) and launcher procurement in addition to funding US science opportunities.It is also jointly responsible for mission performance.


NOAA is expected to provide the US ground stations and operations services.


CNES provides mission expertise and are expected to provide Precise Orbit Determination (POD) services.


The spacecraft carries one main instrument:


  • The Synthetic Aperture Radar Altimeter (POSEIDON-4)


It is complemented by,


Four instruments for Precise Orbit Determination (POD):

  • DORIS: Doppler Orbit Radio positioning system

  • GNSS-POD: GPS/Galileo receiver, providing data for precise orbit determination

  • Star trackers used in support of POD and knowledge of the altimeter pointing

  • LRA: to accurately locate the satellite in orbit using a Laser Retro-reflector Array system

One instrument for water vapour corrections:

  • AMR-C (Climate Quality Advanced Microwave Radiometer): this radiometer is a 3-frequency radiometer complemented by several higher frequency channels to support high-resoluition coastal geophysical parameter retrieval provided by NASA-JPL

As a secondary mission objective:

  • GNSS-RO is an instrument provided by NASA-JPL for the purpose of allowing derivation of atmospheric profiles of pressure and temprature as a function of height by means of radio occultation of GPS signals.

Fig 1-1: Sentinel-6 Satellite and Payloads (Credit: Airbus Defence and Space)