Minimize Mission Summary

 

Figure 1‑3: SENTINEL-6 satellite

 

SENTINEL-6 (JASON-CS) is an operational oceanography programme of two satellites that will ensure continuity to the JASON series of operational missions.

 

SENTINEL-6 makes use of multiple sensing instruments to accomplish its objectives:

 

  • POSEIDON-4 (synthetic aperture radar altimeter)

  • AMR-C (climate quality advanced microwave radiometer) is a multi-frequency radiometer provided by NASA-JPL 

  • DORIS receiver (Doppler Orbitography and Radiopositioning Integrated by Satellite, for POD)

  • GNSS-POD receiver (Global Navigation Satellite System, for POD).

  • Star trackers (for attitude and altimeter pointing knowledge determination)

  • LRA (Laser Retroreflector Array, for POD)

  • GNSS-ROT (GPS receiver provided and developed by NASA-JPL dedicated to radio-occultation measurements).

 

The Posiedon-4, DORIS, AMR-C and LRA are used for topographic measurements of the ocean, coastal areas and in-land water. The altimeter is the main instrument. The AMR-C radiometer provides data for the determination of the total water vapour column content in the atmosphere impacting the radar measurements.

 

 

Mission Details:

 

Mission Objective:

 

The observation missions fall into two categories:

The altimeter mission, ensuring the continuity of the altimeter satellite data services starting with TOPEX/POSEIDON and continued with the JASON mission series. This mission is defined as the prime mission and serves the following users groups:

  • Ocean climate monitoring;

  • Ocean modelling and numerical ocean prediction;

  • Short to mid-term weather forecast;

  • Marine meteorology;

  • Coastal altimetry and modelling.

A secondary mission, consisting of the Radio Occultation (RO) instrument extending the atmospheric sounding of water vapour and temperature profiles used for numerical weather prediction.

 

Mission Duration:

  • 6 months commissioning

  • 5 year operational mission.

Mission Orbit:

  • Type: LEO, non sun-synchronous

  • Repeat cycle: 10 days

  • Mean altitude: 1336 km

  • Inclination: 66°

Spacecraft:

 

The spacecraft design is based on CRYOSAT-2, with necessary adaptations for the higher, mid-inclination orbit, harsher radiation environment, increased payload and to de-orbit within 25 years following completion of operations.

 

  • Deployable solar-array extension flaps
  • Most electronics mounted on nadir plate acting as radiator
  • GaAs solar arrays, with 850 W minimum (end of life)
  • 2x108 Ah Li-ion batteries
  • Attitude: 3-axis stabilised local-normal pointing
  • Mono-propellant propulsion system for deorbiting and orbit maintenance

 

  • Dimensions (flight configuration)     5.13 m x 4.17 m x 2.35 m
  • Dimensions (stowed configuration) 5.13 m x 2.47 m x 2.35 m
  • Mass                                                1440 kg (wet)
  • Power                                              891 W average consumption
  • Data volume: approximately            1200 Gbit/day
  • On-board storage by SSR               496 Gbits (beginning of life)

 

 

Planned Launch Date:

  • Q2 2020

Payload:

POSEIDON-4 (SAR Radar Altimeter):

  • Open burst interleaved mode providing conventional pulse-width limited and SAR altimetry simultaneously

  • Possibility of following a built-in digital elevation model for improved surface tracking

AMR-C (Climate-quality Microwave Radiometer – NOAA/JPL contribution):

  • Multi-channel radiometer for high resolution retrieval of water vapour content over global and coastal ocean.

GNSS POD receiver provides GNSS measurements from GPS and Galileo constellations for precise orbit determination.

 

DORIS enables precise orbit determination, as well as providing on-orbit position to the satellite attitude control.

 

LRA (Laser Retroreflector Array) enables tracking by ground-based lasers (NASA-JPL contribution).

 

GNSS-RO receiver for Radio Occultation (NASA-JPL contribution) using GNSS measurements for RO.

 

Launch vehicle:

The launcher will be procured by NASA-KSC on behalf of NASA-JPL with both launches most likely from Vandenburg California, US. The baseline launchers are Falcon-9, Atlas-4 or Antares.

 

Flight Operations:

Mission control for LEOP and IOV from ESOC. Routine operations will be conducted from EUMETSAT. Two ground stations are currently baselined, at Fairbanks and Kiruna (to be confirmed)

 

RF Links

  • X-band data downlink: 150 Mbps at 8.090 GHz
  • S-band TTC link:          16 kbps uplink,32 kbps downlink

 

Payload Data Processing

Data processing and dissemination is performed at EUMETSAT.

 

Satellite Contractors:

Airbus Defence and Space (Germany) is the prime contractor with a core sub-contractor team consisting of Thales-Alenia Space (France), Ruag (Austria) and Thales Systèmes Aéroportés (France).