Aliens in fiction

One of the most frequently portrayed alien races from our own solar system are the Martians, Mars being the most romanticized of the other planets whose surface conditions are closest to being amenable to life. See Mars in fiction for more details on the red planet's numerous roles.

Popular fictional tales of the first half of the 20th century also includes many fanciful tales of alien races and civilizations on our nearest neighbor, the Moon.

Many of the aliens have been hostile and alien invasion has been a very popular idea in Anglo-Saxon science fiction.

Writers have created a long list of extraterrestrial creatures and intelligent beings. Most common forms of aliens are:

Humanoid Aliens Most aliens are humanoid if not human-like, especially in TV series because actors are human. Humanoids include:

• Atevi[?] of C. J. Cherryh
• Asgard of Stargate SG-1
• Deep Ones of H. P. Lovecraft
• Ewoks and Wookies of Star Wars (furred)
• Fagors[?] of Brian W. Aldiss's Helliconia[?] series
• Greys[?] of UFO folklore
• Kafers[?] of 2300AD[?]
• Klingons of Star Trek
• Martians of Edgar Rice Burroughs's Barsoom series, The Martian Chronicles of Ray Bradbury, Aelita[?], Mars Attacks and many others
• Narn[?] of Babylon 5
• Ortheans[?] ? Mary Gentle[?]: Golden Witchbreed (androgynous until puberty)
• Porquinhos[?] of Orson Scott Card's Speaker for the Dead
• Predator aliens of the Predator movies
• Taelons[?] of Earth: The Final Conflict[?]
• Terrians[?] of Earth 2[?]
• Vineans[?] of Yoko Tsuno[?] (blue skin)
• Vulcans of Star Trek

Near-relatives of mankind In these stories, these aliens are descended from the same ancestors as humanity:

• Gethenians[?] and other races of Ursula Le Guins Ekumen stories
• Darrians[?] of the Traveller role-playing game, known for their small, high-technology polity
• Vilani of the Traveller RPG, known for their bureaucratic tendencies and empire building
• Zhodani[?] of the Traveller RPG, known for their psionic abilities
• in Star Trek: The Next Generation, the episode "The Chase" revealed that all the humanoid races in the galaxy are the result of genetic tinkering by a single humanoid race in the distant past

Feline humanoids This form has been popular. They are usually warrior-like as well:

• Aslan of the Traveller RPG
• Hani[?] of C. J. Cherryh
• Kymnar[?] of FTL:2448[?]
• Kzinti[?] of Larry Niven's Known Space series
• Tran[?] of Alan Dean Foster's Icerigger[?]
• Unnamed aliens in Fritz Leiber's Wanderer

Insectoid Aliens

• The Aliens of the Alien movies
• Cinnrusskin[?] of James White's Sector General[?] series
• Mesklinites of Hal Clement's Mission of Gravity[?] (caterpillars)
• Thranx[?] of Alan Dean Foster's Humanx Commonwealth[?] series

Centaurs

• Ishtarians[?] of Poul Anderson's Fire Time[?]
• Tenebrians[?] of Hal Clement's Close to Critical[?]
• Titanides[?] of John Varley's Gaea-trilogy[?]

Reptilians

• Dracs[?] of Barry B. Longyear[?]'s Enemy Mine[?] and The Enemy Papers[?]
• Lithians[?] of James Blish's A Case of Conscience[?]
• Yilane[?] of West of Eden[?] series of Harry Harrison
• the frog-like Gowachin[?] of Frank Herbert's stories
• and various variations of dinosaurs

Parasites and symbionts

• Goa'uld[?] of Stargate SG-1
• the eponymous aliens of The Puppet Masters

Robotic and Mechanical aliens

• Berserkers of Fred Saberhagen[?]'s Berserker series
• Cybermen of Doctor Who
• Cylons[?] of Battlestar Galactica

Ancient Races

Aliens that have either disappeared and left only ruins or developed to godlike- practically omnipotent entities.

• Unnamed aliens in 2001: A Space Odyssey
• Heechee of Frederick Pohl
• See also Arthur C. Clarke's short story "The Star"
• August Derleth's Elder Gods[?]
• The Ancients of Stargate SG-1
• both of Terry Pratchett's early science fiction novels, Strata[?] and The Dark Side of the Sun[?], offer subversions of the paradigm

More unusual forms

• Abyormenites[?] of Hal Clement's Cycle of Fire (floating ballons ? one race, that is)
• Black Cloud[?] of Fred Hoyle (interstellar dust cloud)
• the Caleban[?] of Frank Herbert's Whipping Star (invisible telepathic beings who are actually the minds of stars)
• the Doublers, two-in-one semi-humanoids of Stanislaw Lem's Eden
• Hivers[?] of Traveller RPG (modified starfish)
• Methorians[?] of Barrington J. Bailey[?]'s Zen Gun[?] (gaseous giant-giant dwellers)
• Oankali[?] of Octavia Butler's Xenogenesis[?] series
• Puppeteers of Larry Niven's Ringworld and Known Space series (three legs, two manipulative heads)
• Solaris by Stanislaw Lem (living planet)
• Tralfamadorians[?] of Kurt Vonnegut (The Sirens of Titan[?], Slaughterhouse 5[?])
• Trillions[?] of Nicholas Fisk[?] (small collective crystals)

Shape-shifting aliens

• the shape-shifters of Star Trek: Deep Space Nine
• the Tleilaxu of Frank Herbert's Dune novels

Unintelligent creatures

• The Colour Out of Space[?] by H. P. Lovecraft (disputed)
• Tribbles, from Star Trek

Aliens From other Dimensions

• The Q of Star Trek
• Species 8472 of Star Trek
• Unnamed Telepathic Aliens of Babylon 5: Thirdspace
• Kromags of Sliders
• Digimon of Digimon

• Wayne Douglas Barlowe[?], Ian Summers and Beth Meacham: Barlowe's Guide to Extraterrestrials
• Stanley Schmidt[?]: Aliens and Alien Societies[?] (Writer's Digest)
• Jack Cohen[?] and Ian Stewart[?]: Evolving the Alien ? the science of extraterrestrial life

Related topics

• Alien invasion
• First contact
• Xenobiology