Layers of the Atmosphere Tools A B troposphere layer where weather occurs stratosphere contains the ozone layer mesosphere middle layer; where metors are found thermosphere known for its high temperatures;thickest layer exosphere last layer of the atmosphere; where shuttles orbit Earth ionosphere contains electrically charged particles; found in the mesosphere and thermosphere atmosphere thin layer of air that forms a protective covering around the air therm- prefix that means heat tropo- prefix that means changing exo- prefix that means outer meso- prefix that means middle strato- prefix that means layer