Why does the Earth need an atomsphere

Why does the Earth need an atmosphere?

The Atmosphere is made up gases such as oxygen and Nitrogen that wraps around  

the Earth like a blanket. Our air is made up of 79% Nitrogen and 21% Oxygen,

The Earth's has five layers of the atmosphere exosphere, the thermosphere,

the mesosphere, the stratosphere and the troposphere. For example the thermosphere

is the lowest a layer of the atmosphere. And if we never had an Atmosphere we would

die from the sun's atmosphere. As the Thermosphere extends you will come to the

Stratosphere.

Then it will come to the Mesosphere and extends to 85 kilometers which is 53 miles high.

The temperature goes down to minus 93 degrees celsius so that is why the meteorites burn

up while entering the atmosphere. The Thermosphere just starts above the Mesosphere and

extends 600 kilometers and 372 mile high.