noctilucent cloud

noc·​ti·​lu·​cent cloud | \ ˌnäk-tə-ˈlü-sᵊnt- How to pronounce noctilucent cloud (audio) \

Definition of noctilucent cloud

: a luminous thin usually colored cloud seen especially at twilight at a height of about 50 miles (80 kilometers)

Examples of noctilucent cloud in a Sentence

Recent Examples on the Web The team is the first to demonstrate noctilucent cloud formation is linked to water vapor cooling. Elizabeth Gamillo, Smithsonian Magazine, 10 Mar. 2021 Agencies could educate employees on how to recognize high-altitude balloons hit by moonlight, fireballs that look like floating orbs, noctilucent clouds that resemble extraterrestrial neural networks. Sarah Scoles, Wired, 3 Mar. 2020 But as days get shorter with the onset of fall, noctilucent clouds will fade from view. Andrew Fazekas, National Geographic, 1 Aug. 2019 That water vapor is responsible for the brightening noctilucent clouds, the new study says. Rachel Becker, The Verge, 6 July 2018 Researchers used computer simulations to model the Northern Hemisphere’s atmosphere and noctilucent clouds from 1871 to 2008, according to the study, which was published last week in the journal Geophysical Research Letters. Katie Camero,, 13 July 2018 The first time people reported noticing noctilucent clouds was in 1880s after the massive eruption of Krakatau, a volcano in Indonesia. Rachel Becker, The Verge, 6 July 2018 What caught my eye, and the eyes of several other meteorologists, was the idea that these could be noctilucent clouds, instead. Kathryn Prociv, Washington Post, 30 Mar. 2018 People living in high latitude areas (between 45º and 70º above or below the Equator) have the best chance of seeing noctilucent clouds. Andrew Fazekas, National Geographic, 22 June 2017

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

circa 1934, in the meaning defined above

History and Etymology for noctilucent cloud

noctilucent "luminous in the dark," from Latin noct-, nox night entry 1 + -i- -i- + lucent

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The first known use of noctilucent cloud was circa 1934

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Cite this Entry

“Noctilucent cloud.” Dictionary, Merriam-Webster, Accessed 26 Oct. 2021.

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