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The atmosphere is a layer of air which covers the earth and is 1000 km thick.

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The atmosphere is like a protective shield because it stops the sun's rays from directly

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reaching the earth.

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The atmosphere makes life on our planet possible because it regulates the surface temperature

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of the Earth and it filters radiation from the Sun.

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The atmosphere is divided in five layers.

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From the closest to the surface these are the troposphere, the stratosphere, the mesosphere,

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the thermosphere and the exosphere.

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The troposphere.

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Water vapor and most of the oxygen we breathe is in this layer.

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can find clouds, rain and wind here. The stratosphere. The air forms horizontal

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layers or strata here. It contains the ozone layer which absorbs most of the

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sun's harmful rays. The mesosphere. There is very little air in this layer. We can

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see shooting stars and there is sometimes turbulence here. Spaceships

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returning to Earth start to feel the friction of the atmosphere here.

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The thermosphere. There is very little air and it can be very hot up to 2,000

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degrees centigrade. Many meteorites disintegrate here.

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The exosphere, the transition zone between the Earth's atmosphere and space.

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You can find artificial satellites here.

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This is the mind map that will help you review the layers of the atmosphere.