Grades 6–8 · Flip the cards to explore the troposphere, stratosphere, mesosphere, thermosphere and exosphere.

Layers of the Atmosphere

A blanket of gases around Earth, mostly nitrogen (about 78 percent) and oxygen (about 21 percent).

The troposphere. It reaches from the ground to about 10 kilometers (6 miles) up on average.

Which layer do we live in, where almost all weather happens?

It gets colder. That is why high mountaintops can have snow all year.

What happens to temperature as you climb higher in the troposphere?

The stratosphere, from the top of the troposphere to about 50 kilometers (31 miles) up.

Ozone absorbs ultraviolet light from the Sun, and that energy heats the air.

Why does the stratosphere get warmer as you go higher?

The mesosphere, from about 50 to 85 kilometers up. It is the coldest layer.

The thermosphere, which starts about 85 kilometers up. The space station orbits about 400 kilometers (250 miles) up.

In which layer do auroras glow and the International Space Station orbit?

The exosphere, where the air is so thin that it slowly fades into space.

About as thin as the apple's skin. More than 99 percent of the air lies within about 50 kilometers of the ground.

If Earth were an apple, how thick would the atmosphere be?