The ozone layer is a layer of the Earth's atmosphere that absorbs ultraviolet rays. Although it is important to the health of the planet, it has been eroded by human activity. pollutants destroy the protective ozone layer. The thermosphere is the fourth layer of the Earth's atmosphere. The upper part of the exosphere is located within the orbit of the International Space Station. In the thermosphere, you can see auroras, also known as polar lights. The ionosphere is the layer of the Earth's atmosphere between the stratosphere and the thermosphere