Answer:
The answer is Exosphere.
Explanation:
Firstly, a brief denition of thermosphere:
The thermosphere is a layer of Earth's atmosphere. The thermosphere is directly above the mesosphere and below the exosphere. It extends from about 80 km to between 600 and 800 km above our planet.
The thermosphere is typically about 200° C (360° F) hotter in the daytime than at night, and roughly 500° C (900° F) hotter when the Sun is very active than at other times.
I have attached an image that shows the atmosphere layers
Finally, the top layer of the thermosphere is Exosphere.
