Such is the worldwide admiration for Einstein (i.e., one stone) that everything is conveniently described as being "relative." There is a difference, however, between Einstein's special theory of relativity and the concept of relative motion as it applies to our everyday experience. This relative motion business can be grasped without any of the mathematical manipulations that would be necessary with Einstein's theory. (By the way, Einstein's SR was proven wrong by many physicists, most noteably Dingle, Poor and Ives.) Neville. "Cheryl B." <c.battles@xxxxxxxxxxx> wrote: I meant to respond to Philip, not Dan, on the relativity thing. As I said to Dan, there is a site that shows what we would see if we were on the moon, far out in space looking down on the earth as it revolved around the earth, etcetera. There is an expectation of what you would see from the moon based on what Copernicus said. So if the astronauts got to the moon and did not see the earth budging one single inch, well then? And would they not be in a position to say yes or no? Based on the theory, they could verify if that theory was correct or not. They would be standing on the moon and should see the earth going through phases and see the earth turning completely every 24 hours -- relativity or no relativity. Yes? --------------------------------- ALL-NEW Yahoo! Messenger - all new features - even more fun!