An Earth Explorer
Launched on 22 November 2013, Swarm is ESA’s latest Earth Explorer in space. Developed in response to pressing scientific challenges, Earth Explorer missions offer new observational capabilities to understand different aspects of the Earth system and the impact human activity is having on natural processes.
The first Earth Explorer, GOCE, was launched in March 2009. It mapped variations in Earth’s gravity with unrivalled precision. The result is the most accurate shape of the ‘geoid’ – a hypothetical global ocean at rest – ever produced, which is being used to understand ocean circulation, sea level, ice dynamics and Earth’s interior. The satellite's life in space came to a natural end when it ran out of fuel in 2013.
SMOS and CryoSat, currently in orbit, provide new information on soil moisture and ocean salinity, and ice, respectively. Not only are these versatile missions meeting their original goals, but they have surpassed expectations with a range of interesting and complementary results.
Continuing in the same vein, Swarm is dedicated to identifying and measuring, very precisely, the different magnetic signals that stem from Earth’s core, mantle, crust, oceans, ionosphere and magnetosphere – which together form the magnetic field around Earth.