Fotografie di nuvole 'lucenti' fotografate da un satellite NASA

clipped from www.foxnews.com Satellite Gets Pictures of Mysterious Shining Clouds A new NASA satellite has recorded the first detailed images from space of a mysterious type of cloud called "night-shining" or "noctilucent." "It is clear that these clouds are changing, a sign that a part of our atmosphere is changing and we do not understand how, why or what it means," said atmospheric scientists James Russell III of Hampton University in Hampton, Va. "These observations suggest a connection with global change in the lower atmosphere and could represent an early warning that our Earth environment is being changed." The "Aeronomy of Ice in the Mesosphere" (AIM) satellite first imaged the noctilucent clouds May 25. People on the ground began seeing them June 6 over Northern Europe. The puffs of water vapor and crystals appear during summer months above the Northern Hemisphere's pole as well the Southern Hemisphere's pole in summer.