A little more than a year after launch, the rich stream of data flowing from EarthCARE is already helping scientists unravel the complex interplay between clouds, aerosols and the climate. To make this possible, the satellite relies on a sophisticated ground station network. This infrastructure enables spacecraft operations, communication links, and the flow of data from orbit to scientists worldwide.
Responsible for launcher tracking, launch and early orbit communications, on-orbit connectivity, re-orbit operations, and data reception – as well as future de-orbit maneuvers – SSC is an important contributor to this effort. Using two of its high-latitude ground stations, gigabytes of EarthCARE observations is downlinked every day, enabling dissemination of invaluable data to the scientific community.
Image: The features and objectives of the EarthCARE mission. Image credit: ESA
Image: Tropical Cyclone Vince as seen by EarthCARE. Image credit: ESA
Guiding EarthCARE through LEOP
Well before EarthCARE entered operations, SSC began its contributions to the mission by supporting its launch and early orbit phase (LEOP).
A joint venture between ESA and the Japanese Aerospace Exploration Agency (JAXA), EarthCARE was lofted into orbit in May 2024. It carried with it a suite of four instruments designed to measure how clouds and aerosols reflect incoming solar radiation and trap outgoing infrared energy. These processes play a crucial role in regulating Earth’s climate.
Taking place directly after lift-off, LEOP involved steering EarthCARE into its intended orbital position. For this, SSC provided a steady uplink from the ground to the satellite, allowing ESA to communicate with the spacecraft and send commands to start up the onboard systems.
These activities were coordinated by ESA and involved expert teams at SSC’s partner station in Hartebeesthoek in South Africa. ESA’s own station Salmijärvi in Kiruna, as well as its mission control center in Germany and other partner stations around the northern hemisphere, also played an important role.
Angelique Bertilsson, Project Manager at SSC, said: “As the ground station partner, SSC supports ESA during LEOP with our antennas to acquire, uplink and provide information that guides ESA to calculate and put the spacecraft into orbit. For EarthCARE, we acquired first acquisition with the spacecraft with our partner station and team in Hartebeesthoek, the first contact after separation from the rocket. Once the spacecraft was located, it really was a team effort to keep steady contact during its laps around the globe.”
“This is something we do often, but every mission has its unique characteristics which we need to adapt to. For EarthCARE, a challenge was the satellite’s low orbit close to the horizon which made it a bit more difficult than normal for our antennas to quickly find the spacecraft and connect.”
Following LEOP, EarthCARE’s instruments were gradually powered up. Within a few months of launch, each of these sensors was operational and ready to begin delivering data to users.
Photo: EarthCARE launch onboard a Falcon 9 rocket from Vandenberg Space Base. Photo credit: ESA
Terabytes of data flow to Earth
Along with other teams on the ground, SSC is responsible for collecting raw data sent to Earth by EarthCARE, downlinked via ground station antennas, up to 13 meters in diameter, located at the Esrange Space Center in Sweden (Lat 67°53′ N, Long 21°04′ E) and the Inuvik Satellite Station Facility in Canada (Lat 68°24′ N, Long 133°30′ W).
Once downlinked, this raw data is processed by SSC at the organization’s network operations center before being disseminated to ESA for further decoding. Approximately 1.5 gigabytes of data are downlinked by SSC per EarthCARE pass, with 15 passes occurring daily. Since the start of the mission, more than 37 terabytes of data have been downlinked from the satellite.
Angelique Bertilsson continued: “As the only provider of X-band support for this mission, we downlink this valuable data from the satellite to the ground, process it and disseminate the information to ESA. Since the mission started, we have covered more than 4,300 passes of the satellite, and this never-ending flow of information is already starting to give us insights into how clouds affect the temperatures down on Earth. Offering this link between the satellite and Earth to such an important mission is truly motivating.”
Following the release of Level 1 and Level 2 EarthCARE products in January and March 2025, respectively, scientists have already begun to test out applications of the mission’s observations.
During its first year, the satellite delivered new insights into Earth’s energy balance, stared into the eye of a tropical cyclone, and supported efforts to improve weather forecasting models. Beyond its core objectives, the mission produced some unexpected findings – including detecting large swarms of insects and ocean phytoplankton.
Photo: One of 30+ antennas at Esrange Space Center in northern Sweden.
Ground station collaboration set to continue
EarthCARE was originally planned to complete operations in 2028, but a recent analysis of available fuel suggests that it could remain operational until 2034 and possibly beyond. This potentially elongated lifespan is partly due to the accuracy of the orbital insertion, achieved during LEOP with the support of SSC.
With an extended EarthCARE mission now on the cards, the collaboration between ESA and SSC could continue for many more years, yielding a wealth of additional data and greatly enhancing the mission’s scientific impact.
Angelique Bertilsson concluded: “We have a long heritage from supporting various climate programs within ESA’s mission portfolio. What sets the EarthCARE mission apart from many others is the low orbit and high speed of the satellite. In order to effectively track the satellite, we have created a dedicated algorithm which helps our antennas to find the signal and auto-track the spacecraft. As for most other missions, this is a huge collaboration involving individuals at SSC and ESA who each offer a piece of the puzzle to make such a large project successful.”
Björn Frommknecht, ESA’s Missions Manager for EarthCARE, added: “I am very happy to see how the excellent collaboration between SSC and ESA allows to provide these vital data to our user communities. Especially for numerical weather prediction, low latency is key, therefore a flawlessly working downstream chain is essential.”
Read more about EarthCARE: https://earth.esa.int/eogateway/missions/earthcare
