Kühlungsborn, 29.09.2026 - The Keystone satellite mission concept, in which the Leibniz Institute of Atmospheric Physics is also involved, has cleared another hurdle: the European Space Agency (ESA) has selected Keystone, alongside two other concepts, for the next preparatory phase of its twelfth Earth Explorer mission.

Keystone is set to investigate the largely unexplored region of the atmosphere at altitudes of approximately 50 to 250 kilometres. The mission plans to carry out the first-ever global direct measurements of atomic oxygen, supplemented by measurements of temperature, wind and other atmospheric constituents. The data could help to improve our understanding of fundamental processes in this altitude region. Furthermore, the mission is designed to detect metals that enter the atmosphere when space debris re-enters – a topic on which intensive research is also being carried out at the IAP.

In the next phase, Keystone and the two other candidates, ECO and CryoRad, will undergo further development. The decision as to which of the three concepts will be implemented as Earth Explorer 12 is still pending. The launch of the selected mission is scheduled for around 2036.

Illustration: European Space Agency