Re: What is the sky?
Funnily enough, This is not a new idea. Only the other day I read a very old Sci-Fi short story that basically included this idea and expanded on to suggest that it is the presence of the Moon, gradually peeling away the Earths atmosphere over eons of time by flying through it, that is what gave us the atmosphere that we have today rather than the much thicker one of Venus.
Biting the hand that feeds IT
