ther·​mo·​sphere | \ ˈthər-mə-ˌsfir How to pronounce thermosphere (audio) \

Definition of thermosphere

: the part of the earth's atmosphere that begins at about 50 miles (80 kilometers) above the earth's surface, extends to outer space, and is characterized by steadily increasing temperature with height

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Other Words from thermosphere

thermospheric \ ˌthər-​mə-​ˈsfir-​ik How to pronounce thermosphere (audio) , -​ˈsfer-​ \ adjective

Examples of thermosphere in a Sentence

Recent Examples on the Web And the thermosphere above is thin enough that air drag doesn’t burn orbiting satellites. Max G. Levy, Wired, "Researchers Levitated a Small Tray Using Nothing but Light," 12 Feb. 2021 The company, founded by British billionaire Richard Branson, promises to take six passengers to experience a few minutes of weightlessness in the lower thermosphere in its cutting-edge SpaceShipTwo craft. ... Jon Sindreu, WSJ, "Virgin Galactic: To the Thermosphere With Too Much Love," 16 Aug. 2020 The team also simulated the thermosphere and allowed the sizes of impact aerosols to change over time. Nola Taylor Redd, Smithsonian Magazine, "After the Dinosaur-Killing Impact, Soot Played a Remarkable Role in Extinction," 27 Apr. 2020 The goal is to figure out the particle makeup of the thermosphere and ionosphere, known as the neutral atmosphere and map its changing temperatures. Richard Tribou,, "NASA hitches ride on commercial satellite for UCF-led atmosphere study," 26 Jan. 2018 Richard Branson licensed the technology for Virgin Galactic, his space tourism gambit, which aims to start regular visits to the thermosphere by 2012. Carl Hoffman, WIRED, "Virgin Galactic’s Space-Grazing Aircraft Is Ready for Liftoff," 15 Nov. 2009

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'thermosphere.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of thermosphere

circa 1950, in the meaning defined above

History and Etymology for thermosphere

International Scientific Vocabulary

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Time Traveler for thermosphere

Time Traveler

The first known use of thermosphere was circa 1950

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Statistics for thermosphere

Last Updated

27 Feb 2021

Cite this Entry

“Thermosphere.” Dictionary, Merriam-Webster, Accessed 23 Apr. 2021.

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