By Jonathan O'Callaghan Earth's magnetic field is a protective shield for our planet from cosmic radiation, but it's also somewhat of a mystery - scientists aren't sure why it moves and changes in intensity. And now the first set of high-resolution results from Esa’s three-satellite Swarm constellation reveal that the field is actually getting weaker, albeit by a small amount. Measurements made over the past six months confirm the general trend of the field’s weakening, with the most dramatic declines over the Western Hemisphere. Scroll down for video Esa's Swarm constellation of satellites have measured changes in Earth's magnetic field from January to June 2014. These changes are based on the magnetic signals that stem from Earth's core. Shades of red represent areas of strengthening, while blues show areas of weakening, measured in nanoteslas
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Esa's Swarm satellite constellation reveals data on Earth's magnetic field
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The results, presented in Denmark, show the field is weakening in places
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The Western Hemisphere, in particular, is dramatically getting weaker
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But other places, including the east coast of Africa, are becoming stronger
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This is seen by some as a sign the magnetic field will soon reverse
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And areas of different intensity can also be harmful to other satellites
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The three satellites also accurately tracked the magnetic North pole
Launched in November 2013, @placeholder is providing unprecedented insights into the complex workings of Earth’s magnetic field, which safeguards us from the bombarding cosmic radiation and charged particles.