I think that there probably is /has been other intelligent life out there somewhere. The sheer numbers of stars and probable planets with life just in OUR galaxy indicate it is probable, and the number of galaxies in the universe are also in the same range. Billions of billions of galaxies with multi billions of stars.
However, even if there are other civilisations that are at or above our level of technology, the odds that any of them are so close to us that we would be able to attract their attention (say from our radio signals, which at most have reached 110 light years distance, and the earliest were exceedingly weak) are pretty slim. And the fact that we are listening for similar radio signals yet have found none that are regular enough to indicate a similar technology, indicate that either technology such as ours is exceeding rare or that there is a basic flaw in our search /thought process. Intelligent life may be common , but technological intelligent life may only occur in one out of a billion intelligent species. And perhaps even fewer of those survive their technological phase. Those that do, may abandon tech either due to choice or lack of resources to continue it. Or perhaps those that do are "culled" by some other vastly superior technological super species (most likely to be artificial life, which could withstand generational travel methods much better than organic life ...(skynet in spades)
Are we regularly visited by them....NO, due to the vast distances
to be overcome. And the odds that two similarly technological species arise at the same time in the same area (say 1000 light years sphere) and develope a FTL transportation system that would enable one to "visit" the other are almost exceedingly slim. The odds that the visitor would even care to visit the other are also slim.
I do feel that it is possible that the earth may have been visited at some point in the distant past. Perhaps even some genetic, DNA manipulation mave have been done which pushed us in our developement as a species. But this would have been many thousands of years ago, and any real evidence is speculative. And the motive for doing so with a return based on a many thousand year unknown payoff would be pretty slim too.
The really strange thing is I have also seen UFOs, but looking back on it they could have been military secret aircraft, although the types of flight (right angle turns, etc) seen would smear any pilot all over the inside of any manned crafts cockpit. Our government does NOT always tell us what they are doing.
Last edited by ScottXray; 05-05-2010 at 09:57 AM..