AAC Clyde Space has secured a €76.3m (US$88.6m) contract from OHB Sweden to supply microwave radiometers for the EPS-Sterna weather satellite program.
The order covers 20 instruments, which will serve as the primary payload for the next-generation European weather satellites. Work on the contract has started immediately, with the first six units scheduled for delivery by the end of 2028. The remaining instruments will be delivered at a rate of two per year through 2035.
The microwave radiometers, developed by AAC Clyde Space subsidiary AAC Omnisys in Gothenburg, Sweden, measure atmospheric temperature and humidity – data used in numerical weather prediction. The technology has previously been demonstrated on the Arctic Weather Satellite mission.
“We are extremely proud of this program and thank OHB, ESA and EUMETSAT for entrusting us with the supply of the critical payload for this next generation weather mission,” said Luis Gomes, CEO of AAC Clyde Space. “These instruments will improve global weather forecasts, while significantly reducing the cost of weather missions. It is a perfect example of how we connect space technology with benefits that make a difference in our daily lives.”
The EPS-Sterna program is led by the European Space Agency (ESA) on behalf of EUMETSAT, with OHB Sweden acting as prime contractor. The satellite system will consist of six spacecraft operating simultaneously in polar orbit, with additional satellites launched over time to maintain coverage.
Fredrik Sjöberg, managing director of OHB Sweden, said the program reflects collaboration within the European space sector: “EPS-Sterna is an important program for European weather forecasting, and a strong example of Swedish space capabilities.”
The first EPS-Sterna satellite is expected to launch in 2029, with a total of 20 satellites planned over the program’s lifetime through 2042.
According to project data, the system is expected to improve forecast accuracy by around 6% across EUMETSAT member states and up to 9% in the Arctic region.
Microwave radiometers operate by measuring thermal radiation from the Earth and atmosphere at specific frequencies, enabling observations through cloud, rain and snow. The AAC Omnisys instrument includes multiple channels, including the 325GHz band, enabling improved detection of atmospheric moisture and ice formation.
The compact design is intended to support smaller, more cost-efficient satellites while maintaining performance for operational weather forecasting.
Related news, Hyperspectral microwave sounder demonstrator launched to improve weather forecasting