I was replying to nicta, and to his comment about collisions at the fringes of the atmosphere. What is the interaction between rays and molecules? What are solar winds and how do they interact with molecules? Do these collisions give rise to phenomena observable at the (for want, in my case, of the correct term) "macro" level?

But a description in layman's terms of the LHC project would also be welcome.

It occurs to me you may not have ET discussion threads displayed as "nested", meaning that you can see on screen which comment is replying to which. Is that the case?