Extraterrestrial life (popular culture)

Extraterrestrials in fiction

Martian controlled Tripod, from War of the Worlds
Grouping	Mythological Science fiction
Similar creatures	Cryptids
Other name(s)	Aliens, space aliens

Extraterrestrials, a common theme in modern science-fiction, also appeared in much earlier works such as the second-century parody True History by Lucian of Samosata.

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.

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."

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).