The sun is not located in any layer of the Earth's atmosphere. The sun is a star, and it is located in the Milky Way galaxy, approximately 149.6 million kilometers (93 million miles) away from Earth.

The Earth's atmosphere is composed of several layers:

* Troposphere: This is the lowest layer, where we live and where weather occurs.

* Stratosphere: This layer contains the ozone layer, which absorbs most of the harmful ultraviolet radiation from the sun.

* Mesosphere: This layer protects us from meteors, which burn up in this layer.

* Thermosphere: This layer is characterized by very high temperatures due to absorption of solar radiation.

* Exosphere: This is the outermost layer, where the atmosphere gradually fades into space.