Aurora, October 8, 2012. This onset of this aurora was actually predicted two days earlier by the National Oceanic and Atmospheric Administration. A large coronal mass ejection had been observed leaving the surface of the Sun and heading our way. A CME is a huge cloud of solar particles that is flung out into space by the powerful magnetic fields of the Sun. If conditions are right when the CME passes the Earth the particles will interact with the Earth's magnetic field to produce an aurora.
This aurora was active for several hours, and it was one of the best displays of recent years.
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