Drawing of Earth's magnetosphere. Notice that the magnetic field is much larger than the planet!
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The Earth's Magnetosphere

The Earth has a magnetic field with north and south poles. The magnetic field of the Earth is enclosed in a region surrounding the Earth called the magnetosphere. As the Earth rotates, its hot core generates strong electric currents that produce the magnetic field. This field reaches 36,000 miles into space. The magnetosphere prevents most of the particles from the sun, carried in solar wind, from impacting the Earth. The solar wind distorts the shape of the magnetosphere by compressing it at the front and causing a long tail to form on the side away from the Sun. This long tail is called the magnetotail .

Some particles from the solar wind can enters the magnetosphere. The particles that enter from the magnetotail travel toward the Earth and create the auroral oval light shows.

The Sun and other planets have magnetospheres, but the Earth has the strongest one of all the rocky planets. The Earth's north and south magnetic poles reverse at irregular intervals of hundreds of thousands of years. In addition, the poles wander over shorter periods of time (hundreds of years).

Last modified March 29, 2010 by Randy Russell.

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