Ancient astronaut theory is the theory that life on Earth was intelligently designed and put into its place in the cosmos by an extraterrestrial visitor. The theory is generally given little credit and there is no definitive evidence, however its proponents point to ancient texts, sculptures and paintings, some of which depict alien life forms visiting and interacting with humans. Probably the most famous proponent of this view is Erich von Daniken.
This theory is the base of the Raƫlian Church.