According to ancient astronaut theories, intelligent extraterrestrial beings (called ancient astronauts or ancient aliens) have visited Earth and this contact is connected with the origins or development of human cultures, technologies, and/or religions.
Ancient astronaut theories have been widely used in science fiction. Such theories have not received support within the scientific community, and have received little or no attention in peer-reviewed studies from scientific journals.
Ancient astronaut adherents often claim that humans are either descendants or creations of beings who landed on Earth thousands of years ago. An associated theory is that much of human knowledge, religion and culture came from extraterrestrial visitors in ancient times, in that ancient astronauts acted as a “mother culture”. These ideas are generally discounted by the scientific community.
Ancient astronaut theories also may include the idea that civilization may have evolved on Earth twice, and that the visitation of ancient astronauts may reflect the return of descendants of ancient humans whose population was separated from earthbound humans.
Proponents of ancient astronaut theories point to what they perceive as gaps in historical and archaeological records, and to what they see as absent or incomplete explanations of historical or archaeological data. They cite evidence that they argue supports their assertions, notably, archaeological artifacts that they argue are anachronistic or beyond the presumed technical capabilities of the historical cultures with which they are associated (sometimes referred to as "Out-of-place artifacts"); and artwork and legends which are interpreted as depicting extraterrestrial contact or technologies.
Scientists maintain that gaps in contemporary knowledge of the past do not demonstrate that such speculative ancient astronaut ideas are a necessary, or even plausible, conclusion to draw. The scientific community remains generally skeptical, and the dominant view is that there is no evidence to support ancient astronaut and paleocontact theories.
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 and unproven.
Shklovski and Sagan argued that sub-lightspeed interstellar travel by extraterrestrial life was a certainty when considering technologies that were established or feasible in the late '60s; that repeated instances of extraterrestrial visitation to Earth were plausible; and that pre-scientific narratives can offer a potentially reliable means of describing contact with outsiders. Additionally, Shklovski and Sagan cited tales of Oannes, a fishlike being attributed with teaching agriculture, mathematics and the arts to early Sumerians, as deserving closer scrutiny as a possible instance of paleocontact due to its consistency and detail.
In his 1979 book Broca's Brain, Sagan suggested that he and Shklovski might have inspired the wave of '70s ancient astronaut books, expressing disapproval of "von Däniken and other uncritical writers" who seemingly built on these ideas not as guarded speculations but as "valid evidence of extraterrestrial contact." Sagan argued that while many legends, artifacts and purported OOPArts were cited in support of ancient astronaut theories, "very few require more than passing mention" and could be easily explained with more conventional theories. Sagan also reiterated his earlier conclusion that extraterrestrial visits to Earth were possible but unproven, and perhaps improbable.
|Intelligent extraterrestrials visited the Earth in ancient times and profoundly affected the development of human civilization.|
|Related scientific disciplines|
Erich von Däniken
|Robert K. G. Temple, Zecharia Sitchin, Richard C. Hoagland, Burak Eldem|
Ancient astronaut theories have been advanced by the following authors (listed by year of initial publication):
Erich von Däniken was a leading proponent of this theory in the late 1960s and early 1970s, gaining a large audience through the 1968 publication of his best-selling book Chariots of the Gods? and its sequels.
Certain artifacts and monumental constructions are claimed by von Däniken to have required a more sophisticated technological ability in their construction than that which was available to the ancient cultures who constructed them. 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, the Moai of Easter Island, the Great Pyramid of Giza, and the ancient Baghdad electric batteries.
Von Däniken claims that ancient art and iconography throughout the world illustrates air and space vehicles, non-human but intelligent creatures, ancient astronauts and artifacts of an anachronistically advanced technology. Von Däniken also claims that geographically separated historical cultures share artistic themes, which he argues imply a common origin. For one such example, is von Däniken's interpretation of the sarcophagus lid recovered from the tomb of the Classic-era Maya ruler of Palenque, Pacal. Von Däniken claimed the design represented a seated astronaut, whereas the iconography and accompanying Maya text identifies it as a portrait of the ruler himself with the World Tree of Maya mythology.
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 and the aliens themselves to be gods. Von Däniken claims that the oral and written traditions of most religions contain references to alien visitors in the way of descriptions of stars and vehicular objects travelling through air and space. One such is Ezekiel's revelation in the Old Testament, which Däniken interprets as a detailed description of a landing spacecraft.
Critics argue that von Däniken misrepresented data, that many of his claims were unfounded, and that none of his core claims has been validated.
Zecharia Sitchin's series The Earth Chronicles, beginning with The 12th Planet, revolves around Sitchin's interpretation of ancient Sumerian and Middle Eastern texts, megalithic sites, and artifacts from around the world. He theorizes the gods of old Mesopotamia were actually astronauts from the planet "Nibiru", which Sitchin claims the Sumerians believed to be a remote "12th planet" (counting the Sun, Moon, and Pluto as planets) associated with the god Marduk. According to Sitchin, Nibiru continues to orbit our sun on a 3,600-year elongated orbit. Sitchin also suggests that the asteroid belt between Mars and Jupiter is the shattered remains of the ancient planet "Tiamat", which he claims was destroyed in one of Niburu's orbits through the solar system. Modern astronomy has found no evidence to support Sitchin's claims.
According to Sitchin, the Sumerians relate how 50 Anunnaki, the inhabitants of Nibiru, came to Earth approximately 400,000 years ago with the intent of mining raw materials, especially gold, for transport back to Nibiru. With their small numbers they soon tired of the task and set out to genetically engineer laborers to work the mines. After much trial and error they eventually created homo sapiens sapiens: the "Adapa" (model man) or Adam of later mythology. Sitchin claims the Anunnaki were active in human affairs until their culture was destroyed by global catastrophes caused by the abrupt end of the last ice age some 12,000 years ago. Seeing that humans survived and all they had built was destroyed, the Anunnaki left Earth after giving humans the opportunity and means to govern themselves.
Robert K. G. Temple's 1976 book, The Sirius Mystery argues that the Dogon people of northwestern Mali preserved an account of extraterrestrial visitation from around 5,000 years ago. He quotes various lines of evidence, including supposed advanced astronomical knowledge inherited by the tribe, descriptions, and comparative belief systems with ancient civilizations such as ancient Egypt and Sumer. His work draws heavily on the studies of cultural anthropologists Marcel Griaule and Germaine Dieterlen.
His conclusions have been criticized by scientists, who point out discrepancies within Temple's account, and suggested that the Dogon may have received some of their astronomical information recently, probably from European sources, and may have misrepresented Dogon ethnography.
Raëlism, or Raëlianism, is a religious movement created by Claude Vorilhon, better known as Raël. Raël claims to have encountered extraterrestrials on a number of occasions. On one such occasion, he claims that he was informed that humans were created by an advanced extraterrestrial humanoid race, the Elohim, using their knowledge of DNA and genetics. The Raëlian movement also argues against evolution and supports human cloning.
Proponents cite ancient mythologies to support their viewpoints based on the idea that ancient creation myths of gods who descend from the heavens to Earth to create or instruct humanity are actually representations of alien visitors, whose superior technology accounts for their reception as gods. Proponents attempt to draw an analogy to occurrences in modern times when isolated cultures are exposed to Western technology, such as when, in the early 20th century, "cargo cults" were discovered in the South Pacific: cultures who believed various Western ships and their cargo to be sent from the gods as fulfillment of prophecies concerning their return.
Flying machines are sometimes mentioned in ancient texts; one example is the Vimanas, flying machines found in the Sanskrit epics of India. These tales range from fantastic aerial battles employing various weaponry, to the mundane relating simple technical information, flight procedure, and flights of fancy. (See also Vaimanika Shastra, a text on Vimanas supposedly "channeled" in the early 20th century.)
In the Biblical Old Testament, the Book of Ezekiel tells of a flying object seen as a fiery whirlwind which when descended to the ground gave the appearance of being made of metal. It is described among other things as a wheel within a wheel containing four occupants, "living creatures", whose likeness was that of man. The passage goes on to say that wherever the wheels went the creatures went, and when the living creatures were lifted up the wheels were lifted up. In chapter 4 of Chariots of the Gods?, entitled, “Was God an Astronaut?” von Däniken refers to the vision of Ezekiel, suggesting Ezekiel had seen a spaceship, a comparison Morris Jessup had made in 1956.
In the Book of Genesis, Genesis 6:1-4 states that "When men began to multiply on the face of the ground, and daughters were born to them, the sons of God saw that the daughters of men were fair; and they took to wife such of them as they chose... The Nephilim were on the earth in those days, and also afterward, when the sons of God came in to the daughters of men, and they bore children to them."
The Nephilim are perhaps children of the fallen angels, although scholars are uncertain. Erich von Däniken sees an extraterrestrial connection in this passage, and suggests that here “we have the sons of God, who interbreed with human beings.” 
Chuck Missler and Mark Eastman argue that UFOs carry the fallen angels, or offspring of fallen angels, the Nephilim of Genesis, who have now returned. They believe it was this interbreeding between the angels and humans that led to what they call “the gene pool problem.” Noah was perfect in his “generations,” that is “Noah’s genealogy was not tarnished by the intrusion of fallen angels. It seems that this adulteration of the human gene pool was a major problem on the planet earth.” 
Von Däniken also suggests that the two angels who visited Lot in Genesis 19 were not angels, but ancient astronauts. They may have used atomic weapons to destroy the city of Sodom. In any case, the other worldly beings acted as if there was a time set for Sodom’s destruction. Von Däniken questioned why God would work on a timetable and why an "infinitely good Father" would give "preference to ‘favorite children,’ such as Lot’s family, over countless others."
In several chapters of the Old Testament God is depicted as traveling as a column of smoke and/or fire and making the sound of a trumpet. These descriptions also describe Yahweh as having a physical presence, rather than an abstraction. Yahweh is described raining lightning and stones down upon the enemies of the Hebrews. However, descriptions of the Hebrew God have also featured protecting wings and outstretched arms in the Psalms, features which may be considered contrary to theories of mechanical manifestations of God.
The apocryphal Book of Enoch tells of similar flying objects and beings called "the Watchers" who have mutinied from "heaven" and descended to earth, but goes further in that Enoch is taken on journeys to various corners of the Earth in the object and at one point even travels to the heavens.
Alleged physical evidence includes the discovery of artifacts in Egypt (the Saqqara Bird) and Colombia-Ecuador, which are claimed to be similar to modern planes and gliders, although these have been interpreted by archaeologists as stylized representations of birds and insects.
More support of this theory draws upon what are claimed to be representations of flying saucers in medieval and renaissance art. This is used to support the ancient astronaut theory by attempting to show that the creators of humanity return to check up on their creation throughout time.
Other artistic support for the ancient astronaut theory has been sought in Palaeolithic cave paintings. Wondjina in Australia and Val Camonica in Italy (seen above) are claimed to bear a resemblance to present day astronauts. Supporters of the ancient astronaut theory sometimes claim that similarities such as dome shaped heads, interpreted as beings wearing space helmets, prove that early man was visited by an extraterrestrial race.
The ancient Nazca lines comprise hundreds of enormous ground drawings etched into the high desert landscape of Peru, which consist primarily of geometric shapes, but also include depictions of a variety of animals and at least one human figure. Many believers in ancient astronauts cite the Nazca lines as evidence because the figures created by the lines are most clearly depicted or only able to be seen when viewed from the air. Writing professor Joe Nickell of the University of Kentucky, using only technology he believed to be available to people of the time, was able to recreate one of the larger figures with a reasonable degree of accuracy.
Evidence for ancient astronauts is claimed to include the existence of ancient monuments and megalithic ruins such as the Giza pyramids of Egypt, Machu Picchu in Peru, or Baalbek in Lebanon, and the Moai of Easter Island. Supporters contend these stone structures could not have been built with the technical abilities and tools of the people of the time and further argue that many could not be duplicated even today. They suggest that the large size of the building stones, the precision with which they were laid, and the distances many were transported leaves the question open as to who constructed these sites. These contentions are categorically rejected by mainstream archeology. Some mainstream archeologists have participated in experiments to move large megaliths. These experiments have succeeded in moving megaliths up to at least 40 tons, and they have speculated that with a larger workforce larger megaliths could be towed with ancient technology. Such allegations are not unique in history, however, as similar reasoning lay behind the wonder of the Cyclopean masonry walling at Mycenaean cities in the eyes of Greeks of the following "Dark Age," who believed that the giant Cyclopes had built the walls.
Other than the proponents' own interpretations of ancient writings and artifacts, there has yet to be found any hard evidence to support the ancient astronaut hypothesis.
Alan F. Alford, author of Gods of the New Millennium, (1996) was an adherent of the ancient astronaut theory. Much of his work draws on Sitchin’s theories. However, he now finds fault with Sitchin’s theory after deeper analysis, stating that: “I am now firmly of the opinion that these gods personified the falling sky; in other words, the descent of the gods was a poetic rendition of the cataclysm myth which stood at the heart of ancient Near Eastern religions.”
A 2004 article in Skeptic Magazine states that von Däniken plagiarized many of the book's concepts from Le Matin des Magiciens, that this book in turn was heavily influenced by the Cthulhu Mythos, and that the core of the ancient astronaut theory originates in H. P. Lovecraft's short stories "The Call of Cthulhu" and "At the Mountains of Madness".
Carla Rueckert is an American author who was known primarily as a psychic and trance medium or spirit medium who channeled a social memory complex named Ra.