It is the first satellite dedicated to studying noctilucent clouds, and made its first observations on May 25, 2007.
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Like an omen from the Book of Revelation, a wispy, silvery-blue noctilucent cloud hovered over Colorado late last month.
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The southerly drift of noctilucent clouds may be the miner's canary of global warming, a signal of bad times ahead.
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Somewhat frequent events are noctilucent clouds near the pinnacle of summer, which can only be seen outside of the city.
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In the decades after Otto Jesse's death in 1901, there were few new insights into the nature of noctilucent clouds.
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:: There has been much speculation that polar mesospheric clouds, sometimes known as noctilucent clouds, are seeded by carbon dioxide crystals.
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In that respect, they look similar to the mesospheric clouds, also known as noctilucent clouds on Earth, which occur about above our planet.
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The Earth presently moves through this plane around January 9 and July 9, when there is an increase in radar-detected meteors and meteor-related noctilucent clouds.
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Just below the mesopause, the air is so cold that even the very scarce water vapor at this altitude can be sublimated into polar-mesospheric noctilucent clouds.
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Because of the need for maximum cooling of the water vapor to produce noctilucent clouds, their distribution tends to be restricted to polar regions of Earth.
