It surrounds the Earth
The troposphere is more than seventy-five percent of the atmosphere. The stratosphere is where most of the clouds and rain is. The mesosphere goes up to about eighty kilometers above the Earth. In the thermosphere the air is very thin and it contains the ionosphere. The last layer, the exosphere, begins at 480 kilometers above Earth and goes out into space. The atmosphere is a barrier against meteors, asteroids, and comets. It also keeps us from burning up in the day and from freezing in the night.