A: Snake is/was reported in context of the viewpoint of the observer. Maybe the observer was just "blown away" by the experience. If you were living in the desert, or jungle, about 7,000 years ago, as you measure time, would you not be impressed if these Reptoid "dudes" came down from the heavens in silvery objects and demonstrated techno-wonders from thousands of years in the future, and taught you calculus, geometry and astrophysics to boot?!?
Q: Is that, in fact, what happened?