Movie courtesy of NASA/GSFC.
Aurora and THEMIS Satellite
The aurora, or Southern and Northern Lights, are beautiful light shows in the skies above Earth's polar regions. Storms in the solar wind flowing from the Sun can trigger geomagnetic substorms in Earth's magnetosphere. Subatomic particles swirl along Earth's magnetic field lines, colliding with gases in our planet's upper atmosphere near the poles. The gases glow, creating the characteristic greens and reds of the auroral displays.
A NASA mission named THEMIS is studying the aurora. THEMIS includes a cluster of five satellites that were launched in February 2007. Twenty ground stations observe aurora in concert with the satellite cluster, providing scientists with numerous viewpoints in their quest to understand the mysteries of the aurora.
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