Spacecraft chases highest clouds

[Rick]

Remarkable new images of Earth's highest and most mysterious clouds have been captured by a Nasa spacecraft.

Noctilucent, or "night-shining", clouds appear as thin bands in twilight skies, some 80km (50miles) above the surface.

The AIM probe has now returned the first truly global pictures of these phenomena which appear to be increasing in frequency and extent.

More: http://news.bbc.co.uk/1/hi/sci/tech/7137905.stm