ESA's SMOS satellite has clocked up more than one billion kilometres orbiting Earth to improve our understanding of our planet's water cycle. Marking its fifth birthday, all the data collected over land and ocean have been drawn together to show how moisture in the soil and salinity in the ocean change over the year.

The Earth Explorer SMOS mission was launched on 2 November 2009 from Plesetsk in Russia.

Carrying a novel sensor, it captures images of 'brightness temperature'. These images correspond to microwave radiation emitted from Earth's surface and can be related to soil moisture and ocean salinity - two key variables in Earth's water cycle.