Swarm Scientific Highlights
Swarm reveals why satellites lose track
28 October 2016
Satellite engineers have been puzzling over why GPS navigation systems on low-orbiting satellites like ESA's Swarm sometimes black out when they fly over the equator between Africa and South America. Thanks to Swarm, it appears 'thunderstorms' in the ionosphere are to blame.
Launched in 2013, the Swarm trio is measuring and untangling the different magnetic fields that stem from Earth's core, mantle, crust, oceans, ionosphere and magnetosphere - an undertaking of at least four years.
As with many satellites, ESA's three Swarm satellites carry GPS receivers as part of their positioning system so that operators keep them in the correct orbits. In addition, GPS pinpoints where the satellites are making their scientific measurements.
However, sometimes the satellites lose their GPS connection. In fact, during their first two years in orbit, the link was broken 166 times.
A paper published recently describes how Swarm has revealed there is a direct link between these blackouts and ionospheric 'thunderstorms', around 300-600 km above Earth.