Earth's magnetic mission
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Watching Earth's magnetic field change

Europe's Swarm space mission is providing an unprecedented view of Earth's protective magnetic field, scientists say.

The three-satellite constellation is now routinely mapping its convulsions, allowing researchers to probe the mechanisms that drive the "invisible shield" in remarkable new detail.

This movie, released this week by the Swarm team, shows changes in the field intensity over 15 years. Red is a strengthening ; blue is a weakening.