noun. the outermost atmospheric layer.
- natural object
Example sentences of the word exosphere
1. Noun, singular or mass
It has no moons, no rings, and an atmosphere so thin that scientists classify it as an exosphere.
It's only the second atmospheric layer – the troposphere is below it and the mesosphere, thermosphere and exosphere extend for hundreds of miles above it.
Auroras occur in the next layer, which is known as the ionosphere, or thermosphere, and finally the exosphere gradually thins and merges with empty space.
4. Noun, plural
The temperature range of the exosphere can reach up to 2,700 degrees Fahrenheit (1,500 degrees Celsius) in the uppermost atmosphere as the thin air transmits little heat.