After Sentinel-3 satellites are launched, the following five months are spent commissioning the satellites to ensure that they are working correctly in orbit. This phase is carried out by ESA’s European Space Operations Centre, ESOC, in Darmstadt, Germany. Once commissioned, ESA passes the in-orbit operations of the satellites to Eumetsat, also in Darmstadt. Housekeeping telemetry and commands are done via ESA’s ground station in Kiruna, Sweden.
While Eumetsat operates the satellites, ESA plays a supporting role by monitoring the health of the satellites, including the platform and instruments, and by providing specific services such as the Kiruna S-band ground station and backup flight control centre.
Once the Sentinel-3 data have been acquired, they are sent to the ground and received at the ESA operated X-band core station in Svalbard, Norway. A network of processing and archiving centres systematically process the data. ESA is responsible for the operations of the Sentinel-3 ground segment for land-related core products and for continuously monitoring the quality of the mission’s data. Eumetsat takes care of the provision of marine core products.
All core products are archived and disseminated online to the users.
While the ground segment of each Sentinel mission includes specific components, all the related facilities are united to form the Copernicus Space Component (CSC) Ground Segment. In particular, access to the CSC data is coordinated for ESA through the CSC Data Access System.
Here, data flowing from the various ground segments and missions are streamlined in a way that is as transparent as possible to the users. Eumetsat distributes the marine core products through the EUMETCast System.
The CSC Ground Segment is complemented by the Sentinel Collaborative Ground Segment, which supports national use of Sentinel data from ESA Member States. This entails additional elements for specialised solutions in different technological areas such as data acquisition, complementary production and dissemination, innovative tools and applications, and complementary support to calibration and validation activities.
The CSC Ground Segment and the Data Access Coordinated System are coordinated by ESA (and Eumetsat for the relevant Sentinel missions) , while the Sentinel Collaborative Ground Segment is funded and managed by third parties such as national space agencies.