OHB Sweden to Build Sterna Weather Constellation

Why It Matters

Sterna’s high‑frequency atmospheric data will sharpen European weather models, reducing forecast errors for extreme events and bolstering climate‑resilience. The program also reinforces Europe’s leadership in space‑based meteorology.

Key Takeaways

• ESA contracts OHB Sweden for 20 Sterna satellites.
• Six operational satellites, refreshed twice, plus two spares.
• First launch targeted for 2029, service through 2042.
• Enhances Arctic humidity data, boosting severe weather forecasts.
• New Space approach cuts development time and budget.

Pulse Analysis

The Sterna constellation reflects a broader shift toward agile, cost‑effective satellite programs that can keep pace with accelerating climate change. Traditional polar‑orbiting missions, such as MetOp, have long provided valuable data but often involve lengthy development cycles and hefty budgets. By adopting a New Space model—leveraging modular designs, rapid prototyping, and commercial‑grade components—OHB Sweden can deliver a full‑scale constellation in under a decade, a timeline that aligns with the urgent need for more frequent atmospheric observations.

At the heart of Sterna’s value proposition is its cross‑track scanning microwave radiometer, which captures detailed vertical profiles of atmospheric humidity and temperature. These measurements are critical for assimilating water‑vapour dynamics into numerical weather prediction models, especially over the Arctic where rapid moisture fluctuations drive large‑scale weather patterns. Early data from the Arctic Weather Satellite prototype have already been integrated into ECMWF forecasts, demonstrating tangible improvements in forecast skill. Scaling this capability across a constellation ensures global coverage, reducing blind spots and enhancing the accuracy of severe‑weather warnings for regions like the Mediterranean, which are increasingly vulnerable to extreme events.

Strategically, the partnership between ESA, OHB Sweden, and Eumetsat positions Europe to compete with U.S. and Chinese meteorological satellite programs. By delivering a reliable, long‑term data stream through 2042, Sterna supports not only operational forecasting but also climate‑research initiatives that require consistent, high‑resolution observations. The contract’s emphasis on spares and periodic replenishment underscores a commitment to sustainability and resilience, ensuring that Europe maintains uninterrupted access to critical weather data in an era of heightened climate volatility.