• Digg
  • del.icio.us

Noctilucent Clouds

Credit: Credit & Copyright: Pekka Parviainen (Polar Image) /NASA, Posted on: Monday, 16 June 2003, 06:00 CDT Download full size image

Sometimes it's night on the ground but day in the air. As the Earth rotates to eclipse the Sun, sunset rises up from the ground. Therefore, at sunset on the ground, sunlight still shines on clouds above. Under usual circumstances, a pretty sunset might be visible, but unusual noctilucent clouds float so high up they can be seen well after dark. Pictured above, a network of noctilucent clouds casts a colorful but eerie glow visible above the dark. Although noctilucent clouds are thought to be composed of small ice-coated particles, much remains unknown about them. Recent evidence indicates that at least some noctilucent clouds result from freezing water exhaust from Space Shuttles.






More Images

Mars
Pitted Layers Northeast of Hellas Region.Pitted Layers Northeast of Hellas Region...

Universe
360-degree Panorama of the Southern Sky.The Milky Way arches across this rare 360-degree panorama of the night sky above the Paranal platfor...



redOrbit Friends


Quiz Me

How often does the moon orbit Earth?
Every 25.5 days
Every 27.3 days
Every 28.8 days
Every 30.6 days
or View Results