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Luminous at night. Used especially of certain high clouds.


(usually of very thin high-altitude clouds in the summer twilight sky) shining at night
ˌnoctiˈlucence n


(ˌnɒk təˈlu sənt)

(of high-altitude clouds) visible during the short night of the summer.
[1885–90; < Latin nocti- =noct-, s. of nox night + -i- + lucent]
noc`ti•lu′cence, n.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.noctilucent - shining or glowing by night; "the noctilucent eyes of a cat"
bright - emitting or reflecting light readily or in large amounts; "the sun was bright and hot"; "a bright sunlit room"
References in periodicals archive ?
Weather satellites have been launched to study noctilucent clouds to determine why they form and how they may be related to global climate change.
com/noctilucent-cloud-season-came-antarctica-earlier-usual-year-nasa-satellite-reveals-2454441) Noctilucent Cloud Season Came Earlier To Antarctica
He presents his collection of color photographs and explanations regarding sky colors, coronas and iridescence, rainbows and cloudbows, glories, shadows, water colors and glitter, halos and pillars, noctilucent clouds and aurora, and colors from polarization.
But higher up, above all the usual clouds, at a height of about 50 miles is a layer known as the mesosphere - and it's here that we can observe a phenomenon called noctilucent clouds.
Samra and his colleagues also received G-force training, space crew resource management and spacesuit training, and completed a comprehensive study on noctilucent cloud science.
The Airborne Lidar and Observations of Hawaiian Airglow 1990 (ALOHA-90) and the Airborne Lidar and Observations of Hawaiian Airglow/Arctic Noctilucent Cloud Campaign 1993 (ALOHA/ANLC-93) measurement programs employed a lidar and ASI to sample GWs extending from the stratosphere into the MLT (Hostetler et al.
The program intends to send trained astronauts to the Mesosphere altitude (at 83 Km) to study noctilucent clouds.
Later we're shown an image one of the staff members, keen astrophotographer Matt Robinson, took of noctilucent clouds from his home in Sunderland, an image of such significance a film crew are due to follow him round for a week.
Using measurements of noctilucent clouds as a guide, Schilling suggested that the mesosphere's height might vary from roughly 100 km at the equator down to 82 km at latitude 60[degrees] north or south.
This analysis should include atmospheric species like ozone water vapour OH sodium and noctilucent clouds and meteroid introduced metals.
ELECTRIC-BLUE CLOUDS: A vast bank of electric-blue clouds has appeared over Antarctica, signaling the start of the season for southern hemisphere noctilucent clouds.