Introduction to the special issue on the ESA's Soil Moisture and Ocean Salinity Mission (SMOS) : instrument performance and first results

The Soil Moisture and Ocean Salinity (SMOS) mission was launched on the 2nd of November 2009 and is one of ESA's Earth Explorer Missions, being research missions dedicated to investigate specific aspects of our Earth System, thus addressing areas of immediate environmental concern. They are meant to explore new territory, both in technological terms as well as scientifically. SMOS is very true to this idea