These clouds appear when ice-crystal-laden clouds for high in the atmosphere, high enough that the sun strikes the clouds while the ground is in darkness.
This photograph was produced by NASA’s Aeronomy of Ice in the Mesosphere project. The AIM satellite is designed specifically to study the phenomenon of noctilucent clouds. The photo is the first one released by the Project. The Project website has a different terrestrial photo, even more striking than the one I posted previously.
It is awe-inspiring, truly, but it is also just ice.
Physical Science
Comments
That can't be a photo of the clouds. They are only about 80 km above sea level. If they were illuminated by sunlight, also parts of the ground below would be in light.
It must be an synthetic image, computed from ice particle measurements. The coast lines are quite as synthetic.
Posted by: Lassi Hippeläinen | January 9, 2008 4:00 AM
It is awe-inspiring, truly, but it is also just ice.
So many things in space are awe-inspiring! Even when you understand the phenomenon involved they can still be beautiful! A Black Hole could be pretty, as long as you don't get too close that is! LOL!
Dave Briggs :~)
Posted by: Dave Briggs | January 9, 2008 4:12 PM