Ancient astronauts is a pseudohistoric concept based on the belief that intelligent extraterrestrial beings visited Earth and made contact with humans in antiquity and prehistoric times. Proponents suggest that this influenced the development of modern cultures, technologies. The idea that ancient astronauts existed is not taken seriously by academics, Ancient astronauts have been widely used as a plot device in science fiction. Proponents of the ancient astronaut hypotheses often maintain that humans are descendants or creations of extraterrestrial intelligence who landed on Earth thousands of years ago. Some ancient astronaut proponents also believe that travelers from outer space, various terms are used to reference claims about ancient astronauts, such as ancient aliens, ancient ufonauts, ancient space pilots, paleocontact, astronaut- or alien gods, or paleo- or Bible-SETI. The evidence is argued to include archaeological artifacts that they deem anachronistic and these are sometimes referred to as out-of-place artifacts, and include artwork and legends which are interpreted in a modern sense as depicting extraterrestrial contact or technologies. Paleocontact or ancient astronaut narratives first appeared in the science fiction of the late 19th to early 20th century. The idea was proposed in earnest by Harold T. Wilkins in 1954, critics of the theory emerged throughout the 1970s, discrediting Von Danikens theory. Ufologists separated the idea from the UFO controversy, by the early 1980s little remaining support of the theory could be found. In their 1966 book Intelligent Life in the Universe, astrophysicists I. S, Shklovski and Carl Sagan devote a chapter to arguments that scientists and historians should seriously consider the possibility that extraterrestrial contact occurred during recorded history. However, Shklovski and Sagan stressed that these ideas were speculative, the contact story was preserved as an oral tradition by the preliterate Tlingit. Over a century after its occurrence it was recorded by anthropologist George T. Emmons. Although it is framed in a Tlingit cultural and spiritual paradigm, according to Sagan, this proved how under certain circumstances, a brief contact with an alien civilization will be recorded in a re-constructible manner. Sagan also reiterated his earlier conclusion that extraterrestrial visits to Earth were possible but unproven, Von Däniken maintains that these artifacts were constructed either directly by extraterrestrial visitors or by humans who learned the necessary knowledge from said visitors. These include Stonehenge, Pumapunku, the Moai of Easter Island, the Great Pyramid of Giza, Von Däniken also claims that geographically separated historical cultures share artistic themes, which he argues imply a common origin. One such example is von Dänikens interpretation of the sarcophagus lid recovered from the tomb of the Classic-era Maya ruler of Palenque, the origins of many religions are interpreted by von Däniken as reactions to encounters with an alien race. According to his view, humans considered the technology of the aliens to be supernatural, one such is Ezekiels revelation in the Old Testament, which Däniken interprets as a detailed description of a landing spacecraft. Von Dänikens hypotheses became popularized in the U. S. after the NBC-TV documentary In Search Of Ancient Astronauts hosted by Rod Serling, critics argue that von Däniken misrepresented data, that many of his claims were unfounded, and that none of his core claims have been validated
Petroglyphs from Val Camonica, Italy. Ancient astronaut proponents assert that these pictures resemble modern astronauts during EVA.
Ancient astronauts proponents suggest that aliens came to Earth long ago, citing artifacts such as this ancient Mesopotamian cylinder seal.
A Dogū figurine from Japan (dated 1000–400 BCE). Ancient astronaut proponents suggest that these may represent extraterrestrial visitors.
Votive relief of the winged priest of Dudu on display at the Louvre Museum, France.