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How did Earth warm enough to support life. New research suggests that the answer lies

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in a perfect coupling between a star and a planet. Today,

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Earth stays warms because carbon dioxide in the atmosphere holds in reflected heat from the

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sun. But four billion years ago, the Earth received less warmth from the sun,

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because the sun was a young star and produced less heat.

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Recent models of our young star show it was much more violent than it is now, constantly

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erupting and sending out huge particle clouds

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Young Earth was different too. It was still growing it's magnetosphere,

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the magnetic shield that protects planets from the sun's forces.

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The magnetosphere's polar caps were far wider than they are now. This

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let particles from the active sun seep into Earth's nitrogen-rich atmosphere.

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The solar particles split up the nitrogen molecules into atoms

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and carbon dioxide in the atmosphere to oxygen and carbon atoms.

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The free-roaming oxygen paired with the nitrogen. The result

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was nitrous oxide, a powerful greenhouse gas.

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Despite the weak contribution from the sun, the planet was able to warm

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enough to brew and incubate life.

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beeping

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beeping