Question: what are the two lowest layers of the atmosphere?
Answer: Troposphere. The troposphere is the lowest layer of our atmosphere. ... 
Stratosphere. The next layer up is called the stratosphere. ... 
Mesosphere. Above the stratosphere is the mesosphere. ... 
Thermosphere. The layer of very rare air above the mesosphere is called the thermosphere. ... 
Exosphere. ... 
Ionosphere.