Thales

Thales Alenia Space has secured a €450m contract from the European Space Agency (ESA) to build Sentinel-3C and D environmental monitoring and oceanographic satellites for Europe’s Earth observation Copernicus programme.

The company previously designed, developed, integrated and tested two identical satellites, which were Sentinel-3A and 3B for the Copernicus programme.

Suitable for the European light launcher Vega, the two Sentinel satellites will be equipped with four main instruments, including two optical instruments and two radar instruments.

An ocean and land colour instrument (OLCI), one of two optical instruments to be carried by the satellites, will be used to monitor the colour of the oceans.

The other optical instrument is a sea and land surface temperature radiometer (SLSTR).

Sentinel-3C and D’s radar instruments include a synthetic aperture radar altimeter (SRAL) and a microwave radiometer (MWR), which will be used to provide multiple capability of surface topography measurement with a primary mission over the oceans, as well as sea ice, ice and in land water.

"An ocean and land colour instrument (OLCI), one of two optical instruments to be carried by the satellites, will be used to monitor the colour of the oceans."

Scheduled to be launched from 2021, the Sentinel-3C and 3D satellites will become anessential part of Europe’s Copernicus programme, managed jointly by ESA and the European Commission.

With the Copernicus programme, Europe intends to receive and manage the Earth’s environmental data in order to support European authorities and decision makers.

Weighing1.2t each during launch, both Sentinel-3C and 3D will be placed in low Earth orbit at 815km altitude. The Sentinel-3 mission also aims to measure the height of oceans.

ESA’s Sentinel programmes will include six satellites, each equipped with instruments for their designated missions.

Sentinel-3 will ensure continuity with optical observation data provided by Envisat, an out of use Earth-observing satellite still in orbit. Sentinel-3A is scheduled for launch by 16 February and the Sentinel-3B is scheduled to be launched by mid-2017.

French space agency CNES and other industry partners are also involved in the programme.

Image: Sentinel-3A is scheduled for launch on 16th February. Photo: courtesy of ESA.