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tone

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music

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In this visualization, Earth's magnetic field structure is represented by lines. It

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corresponds to the paths that charged particles would travel close to the Earth.

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The sun's magnetic field, carried in the plasma of the solar wind,

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flows continuously by the Earth, distorting the planet's field,

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and pulling it back into a windsock-type structure.

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The red illustrates the higher density plasma that forms the magnetopause,

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the boundary between the magnetic influence of the sun and the Earth.

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The wind also forms a lower density magnetotail behind the Earth,

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represented by blue in this computer model. This process

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is happening all the time, as the solar wind is constantly flowing by

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the Earth. But a coronal mass ejection or CME can change

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things. The higher density plasma and stronger

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magnetic field, carried within the CME, strikes Earth's field

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and significantly alters the structure.

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The dramatic changes in Earth's magnetic field and the shape of the magnetopause

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as the CME passes Earth.

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Close to Earth, the magnetic field is largely unchanged. Earth is protected from the intense

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solar event. This for a rather ordinary

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CME. In this example, a CME launched by an X3 flare

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from December 2006. But what would happen in the case of a more

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intense event, such as the Carrington event of 1859.

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With the aid of similar computer models as before, we can explore some of the

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possibilities. Here, a much stronger CME

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compresses the magnetic field between the sun and Earth and generates more density

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in the bow shock, represented by darker red.

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The front of the magnetopause was pushed much closer to the Earth than usual.

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Even the field and plasma trailing behind the Earth are

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more strongly distorted.

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beeping

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beeping