Message posted by Mark Lincoln on July 11, 2011 at 20:43:17 PST:

They were visible 50 years ago despite the lack of any space shuttle or large rockets.

Noctilucent clouds have been observed for over 100 years. They MIGHT be a results of post-industrial revolution pollution, but that is neither proven or supported by any hypothesis. It is simply an empirical observation caused by the fact that they were not reported before about 1885.

The existence of these clouds long before the invention of high-altitude flight, rocketry, and space flight coupled with an increasing occurrence despite the changes in such flight activities suggests that there is no relationship between Moctilucent Clouds and flight/space flight related activity.

Most involved in weather/high altitude research believe the increase in sightings are related to industrial activities and resultant climate change though this is not proven.

In Reply to: Re: OT Noctilucent Clouds (NLC) posted by Gimbal on July 09, 2011 at 2:07:09 PST:

Replies: