The contract was signed Tuesday in Berlin by Volker Liebig, ESA's director of Earth observation; Evert Dudok, chief executive officer of Astrium Satellites; and Uwe Minne, Astrium's director of Earth observation and science. Also attending the ceremony was German Chancellor Angela Merkel, ESA Director General Jean-Jacques Dordain and Johan-Dietrich Worner, head of the German Aerospace Center.

As the project's prime contractor, Astrium will be responsible for the satellite's design, development and integration.

The mission, developed in co-operation with the Japanese Aerospace Exploration Agency, will also address the need for a better understanding of the interactions between cloud, radiative and aerosol processes that play a role in climate regulation.