Spacecraft chases highest clouds

Spacecraft chases highest clouds

news.bbc.co.uk

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.

(visit the link for the full news article)

Does anyone have a theory as to what might be causing this - and whether it ought to be a concern? The BBC article suggests that there is no scientific theory at all with regard to the variation, which seems a bit odd. Does anyone have any knowledge of these phenomena that they would care to share?

In particular, what causes the "holes" they are talking about?



news.bbc.co.uk
(visit the link for the full news article)