Fourth+Period+4.0

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The **TROPOSPHERE **is the ** first ** layer above the surface and contains **HALF ** of the Earth's atmosphere. **Weather** occurs in this layer //. Many jet aircrafts fly in the **__ STRATOSPHERE __** because it is VERY STABLE. Also, the ozone layer absorbs HARMFUL RAYS from the Sun. // **Meteors** or **rock** // fragments ** burn UP ** in the MESOSPHERE. The THERMOSPHERE is a layer with // AURORAS //. It is also where the __ space shuttle orbits __. The atmosphere //merges into space// in the __extremely thin__ E X O S P H E R E. This is the upper limit of our atmosphere.