ionosphere

noun
ion·​o·​sphere | \ ī-ˈä-nə-ˌsfir How to pronounce ionosphere (audio) \

Definition of ionosphere

: the part of the earth's atmosphere in which ionization of atmospheric gases affects the propagation of radio waves, which extends from about 30 miles (50 kilometers) to the exosphere, and which is contiguous with the upper portion of the mesosphere and the thermosphere also : a comparable region of charged particles surrounding another celestial body (such as Venus)

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Other Words from ionosphere

ionospheric \ ˌī-​ˌä-​nə-​ˈsfir-​ik How to pronounce ionospheric (audio) , -​ˈsfer-​ \ adjective
ionospherically \ ˌī-​ˌä-​nə-​ˈsfir-​i-​k(ə-​)lē How to pronounce ionospherically (audio) , -​ˈsfer-​ \ adverb

Examples of ionosphere in a Sentence

Recent Examples on the Web

High-frequency waves can knock out of the magnetosphere to the ionosphere, which creates the green picket fences. David Grossman, Popular Mechanics, "The Science Behind Earth's Strangest Light Phenomena," 29 Apr. 2019 What is surprising, however, is the discrepancies in measurements of how dense the lunar ionosphere is. Daniel Oberhaus, WIRED, "Lunar Mysteries That Science Still Needs to Solve," 16 July 2019 Radio communication has everything to do with the sun and its impact on the ionosphere. Denise Coffey, courant.com, "Ham Radio Operators Practice For Emergencies," 8 July 2019 In an early study for the Navy, Jason devised a communications system for nuclear submarines, first called Bassoon, that bounced low-frequency radio signals off the ionosphere and into the oceans. Ann Finkbeiner, Science | AAAS, "Jason—a secretive group of Cold War science advisers—is fighting to survive in the 21st century," 27 June 2019 Steve is definitely created in the ionosphere, Nishimura’s team reports, but the purple slither doesn’t appear to be an aurora, which is defined as light emissions caused by energetic electrons. Robin George Andrews, National Geographic, "Steve the odd 'aurora' revealed to be two sky shows in one," 3 May 2019 This advance in knowledge matters because typical aurorae and Steve’s purple river appear in the ionosphere. Robin George Andrews, National Geographic, "Steve the odd 'aurora' revealed to be two sky shows in one," 3 May 2019 The ionosphere can also be affected by certain big events, including solar flares, volcanic eruptions, lightning—and the massive bombs dropped on Germany during World War II. Jennifer Ouellette, Ars Technica, "World War II bombings weakened upper atmosphere at edge of space," 25 Sep. 2018 Their best guess was that a STEVE originated in the ionosphere, an upper part of the Earth's atmosphere. David Grossman, Popular Mechanics, "The Science Behind Earth's Strangest Light Phenomena," 29 Apr. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'ionosphere.' 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 ionosphere

1926, in the meaning defined above

History and Etymology for ionosphere

ion or ion(ization) + -o- + -sphere

Note: The term was introduced by the British engineer and physicist Robert A. Watson-Watt (1892-1973), apparently first in an unpublished letter (November 8, 1926) to the secretary of the Radio Research Board, a government agency (see Nature, vol. 224, December 13, 1969, p. 1096). Watson-Watt used it in print in the Quarterly Journal of the Royal Meteorological Society, vol. 55 (1929), p. 278.

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Statistics for ionosphere

Last Updated

7 Aug 2019

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Time Traveler for ionosphere

The first known use of ionosphere was in 1926

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More Definitions for ionosphere

ionosphere

noun
ion·​o·​sphere | \ ī-ˈä-nə-ˌsfir How to pronounce ionosphere (audio) \

Kids Definition of ionosphere

: the part of the earth's atmosphere beginning at an altitude of about 30 miles (50 kilometers) and extending outward that contains electrically charged particles

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More from Merriam-Webster on ionosphere

Rhyming Dictionary: Words that rhyme with ionosphere

Spanish Central: Translation of ionosphere

Nglish: Translation of ionosphere for Spanish Speakers

Britannica.com: Encyclopedia article about ionosphere

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