Sky

The sky is that huge blue globe covering the earth. It is made of air and clouds. It is currently 250 miles thick. There are five layers of the sky:

Troposphere: where most clouds are

Stratosphere: where Mt. Everest’s peak is

Mesosphere: where the D-Layer is

Thermosphere: where the rest of the ionosphere is

Exosphere: Basically outer space

The ionosphere is where northern lights appear from those cosmic ray thingies.