Martian controlled Tripod, from War of the Worlds
|Other name(s)||Aliens, space aliens|
An extraterrestrial or alien is any extraterrestrial lifeform; a lifeform that did not originate on Earth. The word extraterrestrial means "outside Earth". The first published use of extraterrestrial as a noun occurred in 1956, during the Golden Age of Science Fiction.
Extraterrestrial life, also called alien life, is life that occurs outside of Earth and that did not originate from Earth. These hypothetical life forms may range from simple prokaryotes to beings with civilizations far more advanced than humanity. The Drake equation speculates about the existence of intelligent life elsewhere in the universe. The science of extraterrestrial life in all its forms is known as exobiology.
The first Golden Age of Science Fiction, often recognized in the United States as the period from 1938 to 1946, was an era during which the science fiction genre gained wide public attention and many classic science fiction stories were published. In the history of science fiction, the Golden Age follows the "pulp era" of the 1920s and 1930s, and precedes New Wave science fiction of the 1960s and 1970s. The 1950s are a transitional period in this scheme; however, Robert Silverberg, who came of age in the 1950s, saw that decade as the true Golden Age.
Extraterrestrials are a common theme in modern science-fiction, and also appeared in much earlier works such as the second-century parody True History by Lucian of Samosata.
Gary Westfahl writes:
Science fiction aliens are both metaphors and real possibilities. One can probe the nature of humanity with aliens that by contrast illustrate and comment upon human nature. Still, as evidenced by widespread belief in alien visitors (see UFOs) and efforts to detect extraterrestrial radio signals, humans also crave companionship in a vast, cold universe and aliens may represent hopeful, compensatory images of the strange friends we have been unable to find. Thus, aliens will likely remain a central theme in science fiction until we actually encounter them.
An unidentified flying object (UFO) is an object observed in the sky that is not readily identified. Most UFOs are later identified as conventional objects or phenomena. The term is widely used for claimed observations of extraterrestrial spacecraft.
The search for extraterrestrial intelligence (SETI) is a collective term for scientific searches for intelligent extraterrestrial life, for example, monitoring electromagnetic radiation for signs of transmissions from civilizations on other planets.
Cosmic pluralism, the assumption that there are many inhabited worlds beyond the human sphere predates modernity and the development of the heliocentric model and is common in mythologies worldwide. The 2nd century writer of satires, Lucian, in his True History claims to have visited the moon when his ship was sent up by a fountain, which was peopled and at war with the people of the Sun over colonisation of the Morning Star.Other worlds are depicted in such early works as the 10th-century Japanese narrative, The Tale of the Bamboo Cutter , and the medieval Arabic The Adventures of Bulukiya (from the One Thousand and One Nights ).
Cosmic pluralism, the plurality of worlds, or simply pluralism, describes the philosophical belief in numerous "worlds" in addition to Earth, which may harbour extraterrestrial life.
The Tale of the Bamboo Cutter is a 10th-century Japanese monogatari containing Japanese folklore. It is considered the oldest extant Japanese prose narrative although the oldest manuscript dates to 1592.
The assumption of extraterrestrial life in the narrow sense (as opposed to generic cosmic pluralism) becomes possible with the development of the heliocentric understanding of the solar system, and later the understanding of interstellar space, during the Early Modern period, and the topic was popular in the literature of the 17th and 18th century.
In Johannes Kepler's Somnium, published in 1634, the character Duracotus is transported to the moon by demons. Even if much of the story is fantasy, the scientific facts about the moon and how the lunar environment has shaped its non-human inhabitants are science fiction.
Johannes Kepler was a German astronomer, mathematician, and astrologer. He is a key figure in the 17th-century scientific revolution, best known for his laws of planetary motion, and his books Astronomia nova, Harmonices Mundi, and Epitome Astronomiae Copernicanae. These works also provided one of the foundations for Newton's theory of universal gravitation.
Somnium is a novel written in 1608, in Latin, by Johannes Kepler. The narrative would not be published until 1634 by Kepler's son, Ludwig Kepler. In the narrative, an Icelandic boy and his witch mother learn of an island named Levania from a daemon. Somnium presents a detailed imaginative description of how the Earth might look when viewed from the Moon, and is considered the first serious scientific treatise on lunar astronomy. Carl Sagan and Isaac Asimov have referred to it as one of the first works of science fiction.
The didactic poet Henry More took up the classical theme of Cosmic pluralism of the Greek Democritus in "Democritus Platonissans, or an Essay Upon the Infinity of Worlds" (1647).With the new relative viewpoint that understood "our world's sunne / Becomes a starre elsewhere", More made the speculative leap to extrasolar planets,
The possibility of extraterrestrial life was a commonplace of educated discourse in the 17th century, though in Paradise Lost (1667)John Milton cautiously employed the conditional when the angel suggests to Adam the possibility of life on the Moon:
Fontanelle's "Conversations on the Plurality of Worlds" with its similar excursions on the possibility of extraterrestrial life, expanding rather than denying the creative sphere of a Maker, was translated into English in 1686.In "The Excursion" (1728) David Mallet exclaimed, "Ten thousand worlds blaze forth; each with his train / Of peopled worlds." In 1752 Voltaire published "Micromegas" that told of a giant that visits earth to impart knowledge and Washington Irving in his novel, A History of New York from the Beginning of the World to the End of the Dutch Dynasty, spoke of earth being visited by Lunarians.
Camille Flammarion (1842-1925) who lived in a time where biological science had made further progress, made speculation about how life could have evolved on other planets in works such as La pluralité des mondes habités (The Plurality of Inhabited Worlds) (1862) and Recits de L'Infini (1872), translated as Stories of Infinity in 1873. Stories written before the genre of science fiction had found its form.
Closer to the modern age is J.-H. Rosny, who wrote the short story Les Xipéhuz (1887), about a human encounter with extraterrestrials who turns out to be a mineral life form impossible to communicate with.
Authors such as H. G. Wells, Olaf Stapledon and Edgar Rice Burroughs wrote both monitory and celebratory stories of encounting aliens in their science fiction and fantasies. Westfahl sums up: "To survey science fiction aliens, one can classify them by their physiology, character, and eventual relationships with humanity":
Early works posited that aliens would be identical or similar to humans, as is true of Edgar Rice Burroughs's Martians (see Mars; A Princess of Mars ), with variations in skin color, size, and number of arms. ... Later writers realized that such humanoid aliens would not arise through parallel evolution and hence either avoided them or introduced the explanation of ancient races that populated the cosmos with similar beings. The notion surfaces in Ursula K. Le Guin's Hainish novels (see The Left Hand of Darkness ; The Dispossessed ) and was introduced to justify the humanoid aliens of Star Trek (who even intermarry and have children) in the Star Trek: The Next Generation episode "The Chase" (1993).
Another common idea is aliens who closely resemble animals.
Among the many fictional aliens who resemble Earth's animals, Westfahl lists:
Westfahl continues, "However, Stanley G. Weinbaum's A Martian Odyssey (1934) encouraged writers to create genuinely unusual aliens, not merely humans or animals in disguise. Olaf Stapledon also populated the universe with disparate aliens, including sentient stars, in Star Maker . Later, Hal Clement, a hard science fiction writer famed for strange but plausible worlds, also developed bizarre aliens in works like Cycle of Fire (1957)."
Articles related to the phenomenon of extraterrestrials in fiction and popular culture:
Articles related to the purported or theorized existence of extraterrestrials:
Extraterrestrial intelligence refers to hypothetical intelligent extraterrestrial life. The question of whether other inhabited worlds might exist has been debated since ancient times. The modern form of the concept emerged when the Copernican Revolution demonstrated that the Earth was a planet revolving around the Sun, and other planets were conversely, other worlds. The question of whether other inhabited planets or moons exist was a natural consequence of this new understanding. It has become one of the most speculative questions in science and is a central theme of science fiction and popular culture.
"Ancient astronauts" refers to the pseudoscientific idea that intelligent extraterrestrial beings visited Earth and made contact with humans in antiquity and prehistoric times. Proponents suggest that this contact influenced the development of modern cultures, technologies, and religions, and even human biology. A common position is that deities from most, if not all, religions are extraterrestrial in origin, and that advanced technologies brought to Earth by ancient astronauts were interpreted as evidence of divine status by early humans.
In ufology, a close encounter is an event in which a person witnesses an unidentified flying object. This terminology and the system of classification behind it were first suggested in astronomer and UFO researcher J. Allen Hynek's 1972 book The UFO Experience: A Scientific Inquiry. Categories beyond Hynek's original three have been added by others but have not gained universal acceptance, mainly because they lack the scientific rigor that Hynek aimed to bring to ufology.
Grey aliens, also referred to as Zeta Reticulans, Roswell Greys, or Grays, are purported extraterrestrial beings whose existence is discussed in ufological, paranormal, and New Age communities and who are named for their unique skin color. Forty-three percent of all reported alien encounters in the United States describe Grey aliens. Such claims vary in every respect, including the nature, origins, moral dispositions, intentions, and physical appearances of the encountered beings, though many of them nonetheless share some noticeable similarities. A composite description derived from this overlap would have Greys as small-bodied beings with smooth grey-colored skin, enlarged hairless heads and large black eyes.
The Flying Saucers Are Real by Donald Keyhoe, was a ground-breaking book that investigated numerous encounters between United States Air Force fighters, personnel, and other aircraft, and UFOs between 1947 and 1950.
In ufology, the psychosocial hypothesis, abbreviated PSH, argues that at least some UFO reports are best explained by psychological or social means. It is often contrasted with the better-known extraterrestrial hypothesis (ETH), and is particularly popular among UFO researchers in the United Kingdom, such as David Clarke, Hilary Evans, the editors of Magonia magazine, and many of the contributors to Fortean Times magazine. It is also popular in France since the publication in 1977 of a book written by Michel Monnerie, Et si les ovnis n'existaient pas?.
Xenoarchaeology, branch of xenology dealing with extraterrestrial cultures, is a hypothetical form of archaeology that exists mainly in works of science fiction. The field is concerned with the study of material remains to reconstruct and interpret past life-ways of alien civilizations. Xenoarchaeology is not currently practiced by mainstream archaeologists due to the current lack of any material for the discipline to study.
The term "exotheology" was coined in the 1960s or early 1970s for the examination of theological issues as they pertain to extraterrestrial intelligence. It is primarily concerned with either conjecture about possible theological beliefs that extraterrestrials might have, or how our own theologies have been or will be influenced by evidence of and/or interaction with extraterrestrials.
The zoo hypothesis speculates on the assumed behavior and existence of technically-advanced extraterrestrial life and the reasons they refrain from contacting Earth. It is one of many theoretical explanations for the Fermi paradox. The hypothesis is that alien life intentionally avoids communication with Earth, and one of its main interpretations is that it does so to allow for natural evolution and sociocultural development, avoiding interplanetary contamination, similarly to people observing animals at a zoo. The hypothesis seeks to explain the apparent absence of extraterrestrial life despite its generally accepted plausibility and hence the reasonable expectation of its existence.
Contactees are persons who claim to have experienced contact with extraterrestrials. Some claimed ongoing encounters, while others claimed to have had as few as a single encounter. Evidence is anecdotal in all cases.
In science fiction and ufology, a Venusian or Venerian is a native inhabitant of the planet Venus. Many science fiction writers have imagined what extraterrestrial life on Venus might be like.
Many works of fiction have featured UFOs. In most cases, as the fictional story progresses, the Earth is being invaded by hostile alien forces from outer space, usually from Mars, as depicted in early science fiction, or the people are being destroyed by alien forces, as depicted in the film Independence Day. Some fictional UFO encounters may be based on real UFO reports, such as Night Skies. Night Skies is based on the 1997 Phoenix UFO Incident.
A UFO religion is any religion in which the existence of extraterrestrial (ET) entities operating unidentified flying objects (UFOs) is an element of belief. Typically, adherents of such religions believe the ETs to be interested in the welfare of humanity which either already is, or eventually will become, part of a pre-existing ET civilization. Others may incorporate ETs into a more supernatural worldview in which the UFO occupants are more akin to angels than physical aliens; this distinction may be blurred within the overall subculture. These religions have their roots in the tropes of early science fiction and weird fiction writings, in ufology, and in the subculture of UFO sightings and alien abduction stories.
In UFOlogy, Nordic aliens are humanoid extraterrestrials purported to come from the Pleiades who resemble Nordic-Scandinavians. Professed contactees describe them as typically male, six to seven feet tall with long blonde hair, blue eyes, and skin tones ranging from fair to tanned. UFOlogist George Adamski is credited with being among the first to claim contact with Nordic aliens in the mid 1950s, and scholars note that the mythology of extraterrestrial visitation from beings with features described as Aryan often include claims of telepathy, benevolence, and physical beauty.
The term insectoid denotes any creature or object that shares a similar body or traits with common earth insects and arachnids. The term is a combination of "insect" and "-oid".
History of alien abduction claims describes assertions or claims that people have experienced alien abduction. Such claims came to international prominence in the 1950s and 1960s, but some researchers argue abduction narratives can be traced to decades earlier. Such abduction stories have been studied by investigators who believe the accounts describe actual, literal interaction with non-human or extraterrestrial entities. Others have investigated alien abduction claims from a more skeptical perspective, arguing they can be best understood as expressions of folklore or various psychological phenomena.
In ufology, cultural tracking is the tendency of UFO reports through time to change their content in line with cultural changes.