Ancient aliens

"If man landed on the surface of moon why couldn't peoples from other planets come to ours" The moon is a mere quarter of a million miles (250,000) away from us. The nearest other solar system to us is almost 18 trillion miles (18,000,000,000,000) away from us, and that is just the closest. Lets say the nearest civilization was a quarter of the way across the galaxy from us, it would be one hundred and fifty trillion miles (150,000,000,000,000) miles away from us. Now lets say the nearest one is in the nearest other Galaxy, Andromeda. It would be....ready for this number?... 18 quintillion miles (18,000,000,000,000,000,000) away from us. Starting to get the idea? It's all about the size of the universe. There may well be other civilizations out there, even more advanced than us. But the laws of physics are stubborn things. The chances of any civilization ever encountering another one in this vast universe are pretty near zero, they are just too spread out and too far from each other. Think of it as two plankton in an ocean. It's a rather sad and depressing thought but it is likely the truth.

It would certainly make sense, why else would pyramids occur on every continent of the earth, even thought those civilizations never hand any connections to eachother? Also, in drawings and ancient artifacts, you can see that many cultures show mysterious looking things like U.F.O.s and "alien" drawings. I think after Roswell, we had even more contact, because look at how fast the technological growth came after that.

Or what about there were two different races long time ago. Then the other one was advanced and invented an spacecraft. They thought that the other race was too violent and moved to an other planet. I read somewhere that there were some block at the middle of the pacific ocean and there were very advanced people and suddenly it vanished.