Stunning displays of the Northern Lights or aurora borealis occurred on May 10. These were caused by a severe geomagnetic storm that hit Earth. This storm resulted from a solar outburst—specifically a coronal mass ejection (CME)—that reached Earth unexpectedly early on Friday afternoon. CMEs are large expulsions of plasma and magnetic field from the sun's corona that, when directed towards Earth, can interact with the Earth's magnetic field. This interaction accelerates particles in Earth’s magnetosphere, causing them to collide with molecules in the atmosphere and emit coloured light
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