Thermosphere

/ˈθɜrmoʊˌsfɪr/ noun

Definition

The layer of Earth's atmosphere extending from about 85 to 600 kilometers above the surface, characterized by rapidly increasing temperatures due to absorption of solar radiation. This layer contains the ionosphere and is where the aurora phenomena occur.

Etymology

From Greek 'thermos' meaning 'heat' and 'sphaira' meaning 'sphere,' named for the high temperatures reached in this atmospheric layer. The term emerged in the mid-1900s as space exploration revealed the thermal properties of the upper atmosphere.

Kelly Says

The thermosphere is where Earth puts on its most dazzling light shows! Solar particles colliding with gases in this layer create the aurora borealis and aurora australis, painting the sky in curtains of green, red, and purple that have inspired human cultures for millennia.

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