How is the Auroral Discharge Powered?

The Aurora

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p5.jpg (39296 bytes)Because Earth has a magnetic field, plasma from the sun cannot come closer than a distance of about 10 times Earth’s radius. Consequently, the solar wind blows around Earth, forming a long cylindrical cavity, called the magnetosphere, which is shaped like a comet. When the solar wind blows, it stretches out the sun’s own magnetic fields until they interact with Earth’s magnetic fields. Some of these magnetic field lines interconnect across the boundary of the magnetosphere. As the solar wind plasma (an electrical conductor) blows across the interconnected magnetic field lines (in the magnetic field), it can create as much as one million megawatts of electric power. By comparison, the largest manmade power plants on Earth can generate only a few thousand megawatts of power each.

 

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