exosphere
1
9.9
- noun
- /ˌɛksoʊˈsfɪr/
- Specialized
:
exosfera
- The exosphere is the final layer of a planet's atmosphere before the vastness of outer space begins.
Examples
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It does have what is known as a surface-bounded exosphere, an atmosphere so thin that its atoms only collide with the surface; they don't even collide with each other.
Academic text (2007) -
The Mercury Planetary Orbiter (MPO) will spend almost all of its time below 600 km altitude, with instruments to measure the planet's composition and exosphere.
Academic text (2007) -
Expect to hit exosphere in five.
-
Then above that you finally get the atmosphere to dissipate through the exosphere and you're eventually then into space.
-
Now for the exosphere.
-
Even the exosphere peters out at about a quarter of the way to geosynchronous orbit.
Blog text (2) -
Past the thermosphere is the exosphere, which is little more than a random loose hydrogen or helium atom every few meters or so.
Blog text (2) -
What amazed Teresa most was that Spivey and his co-conspirators could actually hide such a massive thing up here, in Earth's crowded exosphere.
Fiction book (1990) -
And, except for some minor hiccups, all of MESSENGER's seven instruments are in good shape to start global imaging, chemical mapping of Mercury's surface, and surveys of its topography, exosphere, and magnetosphere.
Academic text (2007) -
Satellites orbit within the exosphere, where the atmosphere is extremely thin and gas molecules rarely collide.
How High
- Specialized
1
9.9
- Specialized
2
9.5
- Specialized
2
9.5
- Specialized
23
6.5
- Specialized
8
7.4
Surface Forms
Morphology
exosphere = sphere (transparent) = exo + sphere
Formed from the productive combining form 'exo-' meaning 'outside' plus 'sphere', so the meaning 'outermost layer/outer sphere' is directly derived.
Etymology
The word exosphere comes from Greek parts exo- meaning 'outside' and sphere meaning 'ball' or 'layer', like in atmosphere. So, the exosphere is the very outer layer of a planet's air where the atmosphere fades into outer space.