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Sentinel-3 spacecraft model.svg
ManufacturerThales Alenia Space[1]
ApplicationsEarth observation
Spacecraft typeSatellite
Launch mass1,250 kg (2,756 lb)[2]
Dimensions3.710 × 2.202 × 2.207 m (12.2 × 7.2 × 7.2 ft)[2]
Power2,100 W[2]
Design life7 years[2]
On order2[3]
Maiden launchSentinel-3A
16 February 2016
Last launchSentinel-3D
≥ 2021[3]
← Sentinel-2 Sentinel-4

Sentinel-3 is an Earth observation satellite series developed by the European Space Agency as part of the Copernicus Programme.[4][5][6] It currently (as of 2020) consists of 2 satellites: Sentinel-3A and Sentinel-3B. After initial commissioning, each satellite was handed over to EUMETSAT for the routine operations phase of the mission. Two recurrent satellites— Sentinel-3C and Sentinel-3D— will follow in approximately 2024 and 2028 respectively to ensure continuity of the Sentinel-3 mission.

The Sentinel-3 mission's objectives are to measure topography, temperature, marine ecosystems, water quality, pollution, and other features for ocean forecasting and environmental and monitoring.


On 14 April 2008, the European Space Agency and Thales Alenia Space signed a €305 million contract to build the first GMES Sentinel-3 in its Cannes Mandelieu Space Center.[7] Bruno Berruti led the team that was responsible for delivering the Copernicus Sentinel-3 satellites from the drawing board into orbit.[8] The satellite platform was delivered to France for final integration in 2013.[9] The communications systems were completed by Thales Alenia Space España in early 2014.[10]

Sentinel-3A was subsequently launched on 16 February 2016 on a Rokot vehicle from the Plesetsk Cosmodrome, located near Arkhangelsk, Russia.[11][12] This first launch was followed by the launch of Sentinel-3B on 25 April 2018, also aboard a Rokot.[13]

The Sentinel-3 mission's main objective is to measure sea-surface topography, land- and sea-surface temperature, and land- and ocean-surface colour with accuracy in support of ocean forecasting systems, and for environmental and climate monitoring.[4][6][5] Sentinel-3 builds directly on the heritage pioneered by ERS-2 and Envisat satellites. Near-real time data will be provided for ocean forecasting, sea-ice charting, and maritime safety services on the state of the ocean surface, including surface temperature, marine ecosystems, water quality and pollution monitoring.[6]

A pair of Sentinel-3 satellites will enable a short revisit time of less than two days for the OLCI instrument and less than one day for SLSTR at the equator. This will be achieved using both Sentinel-3A and Sentinel-3B satellites in conjunction.[11] The satellite orbit provides a 27-day repeat for the topography package, with a 4-day sub-cycle.[6]


Mission objectives are:[4][6]

Mission characteristics


Sentinel-3 will make use of multiple sensing instruments:[4][6]

Satellite operation and data flow

Sentinel-3 is operated by the European Space Operations Centre (ESA) and Eumetsat. The in-orbit operations for Sentinel-3 are coordinated by Eumetsat in Darmstadt, Germany. This includes monitoring the health of the satellite and the instruments, and coordinates housekeeping telemetry and commands at the main flight control center in Darmstadt, Germany. ESA maintains a backup flight control center at a ground station in Kiruna, Sweden. In addition, the ESA operates an x-band core station in Svalbard, Norway. This station is responsible for receiving the data collected by Sentinel-3.[22] The data is then analysed by the Sentinel Collaborative Ground Segment and compiled into the Copernicus Space Component (CSC). The CSC is an earth observation program run by the ESA with the objective of providing high quality continuous monitoring of the earth.[6]


The applications of Sentinel-3 are diverse. Using the collection of sensors on-board Sentinel-3 is able to detect ocean and land temperature and colour change. The Ocean and Land Color Instrument (OLCI) has a 300 m (980 ft) resolution with 21 distinct bands allowing global coverage in less than four days. This sensor can then be used to by researches to do water quality and land-monitoring research.[23] The satellite also has the ability to monitor the temperature of the sea, land and ice through the Sea and Land Surface Temperature Radiometer (SLSTR). Sentinel-3 also had the ability to detect changes in sea-surface height and sea-ice using the synthetic aperture radar altimeter and the microwave radiometer, two of the most complex sensors on the satellite.[23]

The observations acquired by the mission will be used to in conjunction with other ocean-observing missions to contribute to the Global Ocean Observing System (GOOS) which aims to create a permanent system of ocean observation.[23]



  1. ^ a b "Copernicus: Sentinel-3". eoPortal. European Space Agency. Retrieved 21 December 2015.
  2. ^ a b c d "Sentinel-3 Data Sheet" (PDF). European Space Agency. August 2013. Retrieved 17 November 2016.
  3. ^ a b Henry, Caleb (10 February 2016). "ESA Awards Sentinel 3C and D Satellite Contracts to Thales Alenia Space". Via Satellite. Retrieved 17 November 2016.
  4. ^ a b c d "Sentinel 3". European Space Agency. 2015. Retrieved 10 June 2015.
  5. ^ a b Donlon, C.; Berruti, B.; Buongiorno, A; Ferreira, M-H; Femenias, P.; et al. (2012). "The Global Monitoring for Environment and Security (GMES) Sentinel-3 Mission". Remote Sensing of Environment. 120: 27–57. Bibcode:2012RSEnv.120...37D. doi:10.1016/j.rse.2011.07.024.
  6. ^ a b c d e f g "Copernicus: Sentinel-3". European Space Agency. 2015. Retrieved 11 June 2015.
  7. ^ "Contract signed for ESA's Sentinel-3 earth observation satellite". European Space Agency. 14 April 2008. Retrieved 17 August 2014.
  8. ^ "Bruno Berruti: Project Manager". European Space Agency. Retrieved 26 January 2019.
  9. ^ "Bringing Sentinel-3 together". European Space Agency. 6 March 2013. Retrieved 17 August 2014.
  10. ^ "Thales Alenia Space España's contribution to Europe's Sentinel satellites". Thales Alenia Group. 24 April 2014. Retrieved 17 August 2014.
  11. ^ a b "Sentinel-3 - ESA EO Missions". Earth Online. European Space Agency. Retrieved 13 March 2018.
  12. ^ "About the Launch". European Space Agency. Retrieved 19 February 2019.
  13. ^ Clark, Stephen (25 April 2018). "European environmental observer launched by Russian rocket". Spaceflight Now. Retrieved 25 April 2018.
  14. ^ a b "Radiometric Resolution". Sentinel Online. European Space Agency. Retrieved 9 March 2019.
  15. ^ Birks, Andrew; Cox (14 January 2011). "SLSTR: Algorithm Theoretical Basis Definition Document for Level 1 Observables" (PDF). Science & Technology Facilities Council Rutherford Appleton Laboratory: 173.
  16. ^ "OLCI Instrument Payload". Sentinel Online. European Space Agency. Retrieved 19 February 2019.
  17. ^ a b "Sentinel-3 User Handbook". 1.0. European Space Agency. 2 September 2013. GMES-S3OP-EOPG-TN-13-0001. Archived from the original on 5 March 2016.
  18. ^ Kravitz, Jeremy., Mathews, Mark., Bernard, Stewart., Griffith, Derek (2020). "Application of Sentinel 3 OLCI for chl-a retrieval over small inland water targets: Successes and challenges". Remote Sensing of Environment. 237 (Feb 2020): 111562. Bibcode:2020RSEnv.237k1562K. doi:10.1016/j.rse.2019.111562.((cite journal)): CS1 maint: multiple names: authors list (link)
  19. ^ "Instruments". Retrieved 2020-03-06.
  20. ^ a b "Sentinel-3 - Instrument Payload - Altimetry - Sentinel Online". Retrieved 2020-03-06.
  21. ^ "Altimetry Instruments Payload". Sentinel Online. European Space Agency. Retrieved 19 February 2019.
  22. ^ "Data flow". Sentinel-3. European Space Agency. Retrieved 3 April 2018.
  23. ^ a b c "Sentinel-3 stacks up". European Space Agency. 24 April 2014. Retrieved 21 December 2015.