I agree with some of the others. The human race, basically cannot be the only life form. Ok, Einstein's theory of E=Mc2 states that the universe is expanding at a rate of 30 billion cubic light years per second. That's, well that's more than a google of miles per second... How many seconds has it been since the big band,( 12.7 mil years ago) yea, exactly. The universe is so vast, that we can't comprehend it. It's basically physically impossible that were the only life. By the way, it would be very, very likely that Extra Jovians and or Terrestrials have been around a lot longer than the Human race has. O.K, Homo-Sapien as a race has been around for what; less than 75,000 years I believe. Also, the 6th man on the moon ever, has confirmed that the U.S government has been hiding secrets of Extra Terrestrials. Here's the link:
http://washingtontimes.com/news/2009/apr/21/astro... As for the subject of Roswell, well, we will never know.