Swarm

ESA’s Swarm mission uses three satellites launched together on November 22, 2013 to investigate Earth’s magnetic field and the electrical currents associated with its interior and near-space environment. Vector magnetometers measure field direction and magnitude, while absolute scalar magnetometers provide an independent magnitude reference. Sensitive magnetic sensors are mounted on long booms to reduce interference from spacecraft electronics; precise attitude knowledge relates measurements to Earth. Complementary electric-field and other observations support ionospheric and space-weather studies. Separating internal and external field contributions enables research spanning the core, crust, upper atmosphere and magnetosphere.