It"s around this time of year when some lucky people get to witness these rare, wondrous clouds. Known as noctilucent, or "night-shining," clouds, they"re the highest clouds in our sky and are only visible during summer. They"re made up of icy dust glowing at the edge of space, roughly 50 miles above the planet"s surface. The trick to seeing them is to gaze up into the sky at twilight, when sunlight is not reaching the Earth"s surface, but is still shining through the high-altitude noctilucent clouds. These clouds occur more often at high latitudes but have been seen lower than 50° north and south.
Noctilucent clouds
Today in History
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National Park Week begins
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Keep watching the skies
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Happy New Year!
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Poinsettia Day
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April Fools Day
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Cetacean Saturday
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D-Day remembered
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Shark Awareness Day
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An enduring vision
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Jaguar in the Pantanal wetlands
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Pascua Florida Day
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Traffic jam on the caribou highway
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Hello, spring!
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World Book Day
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A cliff-hanging complex of temples
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National Bison Day
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The artists come to Venice
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Vieste, Apulia, Italy
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May the Fourth be with you…
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Yellow-eyed penguins, Moeraki, New Zealand
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A bridge that rocks
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Fall color sweeps across the West
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It’s not a pinecone, it’s a pangolin
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World Turtle Day
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A holiday beacon of light
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It s superb owl Sunday
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Everyone s watching the Perseids
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Blue Lagoon spa, Grindavík, Iceland
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Father s Day
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Tree of many colors