The aliens (from another solar system) were searching the skies with their high-powered scientific telescopes and stumbled upon Earth. Upon closer observation they detected two interesting features about Earth - (1) significant amounts of water on the surface and (2) a stable atmosphere containing oxygen. Based on their analysis they theorized that Earth might be capable of supporting intelligent life. Thus they decided to send an exploratory mission to Earth to seek signs of intelligent life. They landed in Norman, Oklahoma, found no evidence of intelligent life, and went back home. HHD
