Definition of exosphere in English:


Syllabification: ex·o·sphere
Pronunciation: /ˈeksōˌsfir


The outermost region of a planet’s atmosphere.
More example sentences
  • From the bottom of the exosphere the atmosphere has a thickness of 400 km.
  • Since collisions are negligible above the exobase, the molecules in this region, called the exosphere, move along ballistic trajectories under the action of the earth's gravitational field.
  • Then more indicators flashed to life as the ship skimmed the outer exosphere at Mach 27.



Pronunciation: /ˌeksōˈsfi(ə)rik, -ˈsferik/
More example sentences
  • He has evaluated the escape flux averaged over an entire 11-year cycle of solar activity, using satellite data on exospheric temperature.
  • He did not know how much time that his fleet had before the exospheric trap's consequences manifested.

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