exosphere
Noun
Meaning
the outermost atmospheric layer
Source: WordNetSynonyms
Antonyms
Hypernyms
Examples
It consists of oxygen and carbon dioxide in proportion of roughly 5 to 2. The surface density of the exosphere is from 10 5 to 10 6 molecules in a cubic centimeter depending on local temperature.
Orbital characteristics Objects in LEO encounter atmospheric drag from gases in the thermosphere (approximately 80–500 km up) or exosphere (approximately 500 km and up), depending on orbit height.
The relative lack of dust is due to aerodynamic drag from the extended exosphere corona of Uranus.
Earth atmosphere diagram showing the exosphere and other layers.