New EPS-Sterna satellites poised to transform weather observations

27 November 2025

Photo: ESA/Mlabspace

EUMETSAT is nearing full approval of the EPS-Sterna mission, a constellation of polar-orbiting microsatellites designed to deliver an unprecedented stream of microwave observations of atmospheric temperature, humidity and clouds, data essential for more accurate weather prediction.

Supported by 29 of 30 Member States, the mission builds on the proven performance of ESA’s Arctic Weather Satellite (AWS). Launching in 2029, it will provide near-global measurements approximately every five hours, far more frequent than current systems. These high-resolution observations are expected to cut forecast errors by up to 6% across Europe and nearly 9% in the Arctic, offering a major advance in tracking storm development, predicting extreme events and understanding rapid changes in polar regions.

EUMETSAT: Europe backs transformative polar satellite constellation