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According to scientists who monitored its path, an expanding cloud of energized particles ejected from the Sun recently triggered a large storm in the magnetic field that surrounds Earth, brightening the Northern Lights and possibly knocking out a communications satellite.

According to scientists who monitored its path, an expanding cloud of energized particles ejected from the Sun was what recently triggered a large storm in the magnetic field that surrounds Earth, and it brightened the Northern Lights and also possibly knocked out a communications satellite.