Swarm gets ready for flight

Swarm constellation over Earth

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28 October 2013

There is an invisible magnetic field all around us. Although we don’t normally notice it, the Earth’s magnetic field is very important as it protects us from dangerous solar storms and space radiation. Without it, there would be no life on our planet! In order to measure this magnetic force with greater accuracy than ever before, ESA is preparing to send a special mission into orbit called Swarm.

Swarm consists of a constellation of three satellites in three different polar orbits at heights of between 400 and 550 km. Each satellite will measure the strength and direction of the Earth’s magnetic field.

Earth’s stormy heart

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Scientists believe that the magnetic field is created by liquid in Earth’s outer core, but they still don’t fully understand how it is generated and how it changes over time.

For example, the locations of the north and south magnetic poles are continually shifting. The strength of the field also changes. From time to time, the poles actually reverse, so that the present north pole becomes the south pole. At such times, a magnetic compass would point south instead of north! Scientists hope that the Swarm mission will be able to solve these and many other magnetic mysteries.

Swarm will be launched from the Plesetsk Cosmodrome in Northern Russia on 22 November 2013.