noctilucent cloud
noun
noc·ti·lu·cent cloud
ˌnäk-tə-ˈlü-sᵊnt- 
: 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
And about two decades ago, the European Space Agency's Mars Express orbiter observed noctilucent clouds on Mars and went on to make a systematic study.
—
Eric Berger, Ars Technica, 12 Feb. 2025
Perseverance, however, is located further into the northern hemisphere, and has not recorded any noctilucent clouds.
—Andrew Paul, Popular Science, 13 Feb. 2025
A couple of weeks ago, the rover's Mastcam instrument captured a truly stunning view of noctilucent clouds in the skies above.
—Eric Berger, Ars Technica, 12 Feb. 2025
Shot by astronauts aboard the International Space Station (ISS), this view of noctilucent clouds is illuminated through Earth's upper atmosphere by the setting sun, already tucked behind the dark horizon.
—Space.com Staff, Space.com, 1 Jan. 2025
An animation based on data from NASA’s AIM spacecraft shows the sky over Antarctica glowing blue at the start of noctilucent cloud season in the Southern Hemisphere.
—Tom Yulsman, Discover Magazine, 6 Dec. 2016
These conditions are ideal for spotting noctilucent clouds, shimmering blue clouds composed of ice crystals that form in the mesosphere some 50 miles above Earth.
—Justin Grieser, Washington Post, 21 June 2023
Did an earlier-than-normal shift to summer conditions in the lower atmosphere over Antarctica contribute to the early start of noctilucent cloud season there?
—Tom Yulsman, Discover Magazine, 6 Dec. 2016
Initially launched on April 25, 2007, the NASA probe orbited about 370 miles above Earth's surface and studied polar mesospheric clouds, which are also known as night-shining or noctilucent clouds.
—Ariana Garcia, Chron, 21 Mar. 2023
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Eric Berger, Ars Technica, 12 Feb. 2025
Perseverance, however, is located further into the northern hemisphere, and has not recorded any noctilucent clouds.
—Andrew Paul, Popular Science, 13 Feb. 2025
A couple of weeks ago, the rover's Mastcam instrument captured a truly stunning view of noctilucent clouds in the skies above.
—Eric Berger, Ars Technica, 12 Feb. 2025
Shot by astronauts aboard the International Space Station (ISS), this view of noctilucent clouds is illuminated through Earth's upper atmosphere by the setting sun, already tucked behind the dark horizon.
—Space.com Staff, Space.com, 1 Jan. 2025
An animation based on data from NASA’s AIM spacecraft shows the sky over Antarctica glowing blue at the start of noctilucent cloud season in the Southern Hemisphere.
—Tom Yulsman, Discover Magazine, 6 Dec. 2016
These conditions are ideal for spotting noctilucent clouds, shimmering blue clouds composed of ice crystals that form in the mesosphere some 50 miles above Earth.
—Justin Grieser, Washington Post, 21 June 2023
Did an earlier-than-normal shift to summer conditions in the lower atmosphere over Antarctica contribute to the early start of noctilucent cloud season there?
—Tom Yulsman, Discover Magazine, 6 Dec. 2016
Initially launched on April 25, 2007, the NASA probe orbited about 370 miles above Earth's surface and studied polar mesospheric clouds, which are also known as night-shining or noctilucent clouds.
—Ariana Garcia, Chron, 21 Mar. 2023
Cite this Entry
“Noctilucent cloud.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/noctilucent%20cloud. Accessed 23 May. 2025.
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