Satellites map Earth's magnetic field

A trio of European satellites are being sent on a mission to make the most detailed global maps yet of Earth's magnetic field.

Known as Swarm, the three spacecraft should help scientists understand better how the field is generated deep inside the planet, and why it appears to be weakening.

The satellites are being deployed by one of Russia's de-commissioned intercontinental ballistic missiles.

This animation shows this deployment and the configuration the satellites will adopt in space as they make their measurements.

Video courtesy of the European Space Agency.

BBC News