Epsilon Eridani in fiction
The planetary systems of stars other than the Sun and the Solar System are a staple element in much science fiction. Epsilon Eridani is the fifth brightest star (by apparent magnitude) in the riverine southern constellation of Eridanus. An orange star slightly smaller and less massive than the Sun, and relatively close to the Solar System, it is frequently featured in works of science fiction. It is classified as a type K2 star, with the corresponding suggestion that it has a stable habitable zone and is well suited for life. However, one factor which weakens the case for habitability is its youth—as little as 200 million years old—and consequent high levels of ultraviolet emission (see Implied Spaces by Walter Jon Williams, below).
General uses of Epsilon Eridani
Many stars may be referred to in fictional works for their metaphorical or mythological associations, or else as bright points of light in the sky of the Earth, but not as locations in space or the centers of planetary systems.
The constellation Eridanus flows north and south in the night sky, and Epsilon Eridani is one of its more northerly stars (see map), which allows it to be seen from most of the Earth's surface. However, because of its unprepossessing appearance in the sky, and its want of a "good" traditional name to supplement its esoteric Bayer designation, Epsilon Eridani has rarely if ever been used in a general sense, either in traditional mythologies or in the arts and literature that draw inspiration from them.
The star's popularity as a subject of science fiction stems not from its general cultural resonance, but from the astronomical data:
- Its proximity, ~10.5 light-years distant
- Its similarity to the Sun, ~0.82 , spectral type K
- Its technical sounding name, in this context a benefit rather than a detriment
- Its demonstrated capacity to host a family of planets, with at least one confirmed
There follow references to Epsilon Eridani as a location in space or the center of a planetary system, categorized by genre:
- Dorsai! (1960, also published as The Genetic General), and other novels in the unfinished Childe Cycle by Gordon R. Dickson. Donal Graeme, a warrior extraordinaire from the mercenary homeworld Dorsai, and second incarnation of the series' evolutionary superman, launches his meteoric military career with service in several police actions on the vividly drawn planets Harmony and Association lying under the small orange Epsilon Eridani sun (see graphic).
- "Conquest by Default" (1968), a short story by Vernor Vinge originally published in Analog and later included in The Collected Stories of Vernor Vinge (2001). An alien civilization native to Epsilon Eridani II (the planet Miki) arrives in full force at the Solar System to place the third %wrlyg Support Fleet in a parking orbit high above the Earth, their looming presence decidedly intimidating thanks to a significant edge in technology. The Mikin culture is anarchic, acquisitive, cosmopolitan, and wildly diverse. In the story, as told by Scholar Ron Melmwn (a Mikin anthropologist who establishes tentative inter-species rapport with his human counterparts, professor Dahlmann and his daughter Mary), culture shock abounds as men and women interact with visitors who are bent on immigration, trade—and maybe exterminating the human race.
- The Napoleons of Eridanus (1976), The Emperor of Eridanus (1983), and The Eridani Colonists (1984), translations by Stanley Hochman of the French language Eridanus trilogy written by Dr. Claude Pierre Marie Avice, as by Pierre Barbet. A squadron of Napoleonic soldiers is kidnapped by aliens and hustled off to the Epsilon Eridani system, whence they unaccountably conquer a space empire.
- "Singularity" (1978), a short story by Mildred Downey Broxon. A scientific team monitors the last days of the intelligent but radically alien tribes of Epsilon Eridani's frigid second planet, Mancken's World, as a wandering stellar black hole finds its way through the star's planetary system. The hole makes a feast of the gas giant fifth planet but passes nowhere near Mancken's; however on its close encounter with ε Eridani itself, it will raise a storm of huge planet-scouring flares. The natives, whose prescient mythology has left them not unprepared for the event, calmly await the apocalypse along with a lone abandoned—and fearful—human observer.
- Downbelow Station (1981) and other Alliance-Union universe works, novels by C. J. Cherryh. Epsilon Eridani is the site of Viking Station, a space station founded after the discovery of Pell's World in the Tau Ceti system, and which later joins the Union.
- Foundation's Edge (1982), a novel by Isaac Asimov. In this transitional novel between Asimov's Robot novels and his later-set Galactic Empire novels of the Foundation series, the planet Comporellon of Epsilon Eridani (previously named BaleyWorld after Elijah Baley's son Bentley) was the first non-Spacer extraterrestrial planet settled by Earthmen, in the second wave of stellar emigration after the events that wrapped up the robot series.
- Starburst (1982), a novel by Frederik Pohl. A crew of superb human specimens is sent on what they believe is mankind's first voyage to a planet in another star system. Dr. Dieter von Knefhausen knows better—for there is no planet, no place to go, and no place from which to return. In a fabrication recalling the supposedly fake NASA Moon landings of an earlier century Knefhausen has planned it that way. However, by the end of the tale, humans really do reach the stars, as the protagonist Jeron "... [brings] the fleet of golden globes to the third planet of Epsilon Eridani."
- Eon (1985), a novel by Greg Bear. The Solar System is visited by the Stone, a Big Dumb Object[note 1] that appears to be an artifact sent backward in time from a future human civilization. Records left aboard by the futurians suggest that in their remote past—the Earth's present—the asteroid starship, called by them the Thistledown, was dispatched to Epsilon Eridani to found a new home for humankind[note 2] following the devastation of the Earth in a nuclear holocaust, an account that causes understandable present-day consternation. However the Thistledown never fulfilled the mission, instead getting whip-snapped into an alternate universe immediately upon the activation of the Way, an endless jump street her builders somehow managed to embed within her finite confines.
- The Stones of Nomuru (1988) and The Venom Trees of Sunga (1992), novels in the Viagens Interplanetarias series written by L. Sprague de Camp, with collaboration by Catherine Crook de Camp. Kukulkan, a planet in the Epsilon Eridani system, is inhabited by an ancient civilization of intelligent reptilian creatures that has plateaued at a swords-and-steam level of technology. The "Kooks" are honest, honor-bound, and dull in personality; in both novels, the planet serves as the setting for a number of more or less conventional pre-industrial adventures.
- Starquake (1989), a novel by Robert Forward. Dragon's Egg, a neutron star, has wandered into the vicinity of the Solar System and into the ken of Earth scientists. It has some "dazzling" statistics: a surface gravity 67 billion times that of the Earth, soaring mountains as high as a few inches, ruinous starquakes, and tiny intelligent inhabitants whose life processes are accelerated over ours by a factor of almost half a million. Over a period of a day, human observers inadvertently introduce the rudiments of civilization, and within a man's lifetime the "immensely enjoyable" alien cheela have lived a whole history, progressing even to interstellar exploration and leaving the secrets of FTL travel stashed in a conspicuous landmark on a planet of Epsilon Eridani—as a reward for a humanity enterprising enough to get there.
- Shivering World (1991), a novel by Kathy Tyers. Dr. Graysha Brady-Phillips is suffering from a genetic disease that causes early death. When she is offered a position on the newly terraformed Goddard, a refuge from the ecological ruin of the Earth where the average life span exceeds 150 years, she leaps at the chance; the colonists' radical—and illegal—science just might be her only hope for a cure. The world Goddard is accompanied in Epsilon Eridani orbit by the older artificial habitat Copernicus, ensconced in one of the planet's stable LaGrange points. But whole planets are better: "On broader worlds like this—he squinted towards the red sun his people had once called Eps Eridani—a wiser humanity might start again..."
- Worldwar (1994–1996), a tetralogy of novels written by Harry Turtledove. In this revised history, an Earth in the throes of World War II is invaded by a fleet of starships assembled for the purpose by The Race. Only three times in its 50,000-year history has this expansionist species of reptilian aliens organized such an armada, each time with the goal of subduing another civilization: the Rabotev (inhabitants of Epsilon Eridani), the Halessi, and now humanity. However, the invaders are in for a surprise, as their most recent intelligence on the Earth dates from the Middle Ages. Alternate world stories are a specialty of historian Turtledove, whose "thorough understanding of his source material gracefully infiltrates the fun and fantastication."
- Echoes of Honor (1998), a novel in the Honor Harrington series by David Weber. The Havenite Navy launches a devastating barrage of simultaneous surprise attacks on Manticore and her allies. Lester Tourville, in command of the task force attacking Zanzibar, plans a risky maneuver to knock out its orbital installations—but if any of his missiles hit the planet, there'll be hell to pay: "... violation of the Epsilon Eridani Edict’s ban on indiscriminate planetary bombardment was the one thing guaranteed to bring the Solarian League Navy down on any star nation like a hammer." The prohibitions in the Edict stem from the Epsilon Eridani Incident, an early space war atrocity entailing the mass destruction of one of the League's oldest worlds.
- Helm (1998), a novel written by Steven Gould. Agatsu (あがつ, Epsilon Eridani II) is close to Earth-normal, and the rest can be done quite efficiently by tailored terraforming bacteria. The work will be completed just as the refugee ship, carrying most of what remains of Earth's devastated population, arrives to colonize her. The ship, designed for 1000 souls, will carry 4000—at the expense of almost all her cargo. But that's ok: When the bare survival of the race is at stake, such niceties as any technology past knives, ropes, and hammers would be a sheer luxury. With much ingenuity, the colonists proceed to build a civilization from scratch.
- Factoring Humanity (1998), a novel by Robert J. Sawyer. SETI astronomers detect an artificial signal from Alpha Centauri A, the harbinger of a ten-year flood of cryptic data that protagonist Heather Davis devotes her life to deciphering. She finally succeeds, and comes upon plans for a starship that could open up interstellar contact, starting with the "Centaurs." Meanwhile, a single despairing message is received from Epsilon Eridani, easier to translate but much more alarming: "It couldn’t be plainer: biological life, based on carbon, being supplanted by silicon-based artificial intelligence ..." And it turns out that the AI "overminds" of Earth and Alpha Centauri are already in contact. Is humanity on the threshold of an era of limitless exploration—or of extinction?
- Revelation Space (2000– ), and other novels, novellas, and short stories in the Revelation Space universe by Alastair Reynolds. The Epsilon Eridani system includes:
- Yellowstone, home to the universe's most advanced human civilization, and a focal point of the series as a whole (see graphic). During the so-called Belle Epoque (ending with the nanovirus Melding Plague), Yellowstone society is centered in the Glitter Band and in Chasm City.
- Marco's Eye, a moon of Yellowstone (see graphic).
- Tangerine Dream, a gas giant (see above).
- Halo: The Fall of Reach (2001) and Halo: First Strike (2003), prequel novelizations to installments of the Halo series of video games, written by Eric Nylund, and meant to provide back-stories for the popular games. The first novel begins as Covenant forces attack the planet Reach and vitrify the surface, turning its landmasses into glass. In the books (and games) the Epsilon Eridani system hosts a total of six inhabited planets: Reach itself, which had been a stronghold of humanity, second only to Earth itself, Tribute, Beta Gabriel, Circumstance, Tantalus, and Epsilon Eridani IV (see Halo, below).
- Vorpal Blade (2007), a novel written by John Ringo with Travis S. Taylor. William Weaver, PhD. and SEAL Chief Miller are back and Bill got himself a ship! The former SSBN Nebraska has been converted, using mostly garage mechanics and baling wire, into a warp ship ready to go "out there": the ASS Vorpal Blade. Quite by accident, the Epsilon Eridani System is her first destination.
- Implied Spaces (2008), a novel written by Walter Jon Williams. It is the epoch of the technological singularity. Humanity numbers in the hundreds of billions, but only a few million remain in the solar system. Many have traveled on generation starships to establish colonies around other stars, such as Alpha Centauri, Tau Ceti, and Epsilon Eridani, which was a "prime candidate for settlement—a young star with planets, ... surrounded by a cold dust cloud which [someday] would have congealed into an inner system of rocky bodies..." (see graphic) However, the star is unstable, with energy levels that flare and fade unpredictably, and it undergoes a "stellar event"—not quite a nova; more like a "burp"—that is nonetheless enough to burn to a crisp every last colonist.
- Flight 404 (2012), a novella written by Simon Petrie. A distress call from the Bougainvillaea, a large interstellar passenger vessel, has been detected within Epsilon Eridani's planetary system, two hundred million kilometers from the system's main terrestrial planet, Ashé. There is, however, no material trace of the vessel in the indicated location. Charmain Mertz, a transgender pilot raised on Ashé, but who left because of victimization within its conservatively religious society, returns to her home system hoping to learn the secret of the ship's disappearance, and the fate of her sister, a passenger.
- Hyperion Cantos by Dan Simmons, a cycle of four books, where the Epsilon Eridani system contains a planet colonized by humans. For more information, read the books.
- Attenuation: Letters from the Man in the Moon (2014) by Keith Basham, where Epsilon Eridani is the target of a half million years of attempts at colonization, while a lone pilot known only as 'Larry' goes about the business of fast-tracking the system's accretion process, rendering habitable worlds and a more Sol-like star from Epsilon Eridani. Larry does his best to keep in touch with his home world, but finds that his very existence has been long forgotten, though the star itself has been rechristened in his name. By the time he is done, There are apparently four Earth-like planets constructed in the habitable zone, with one working colony overseen by Larry himself, whose ship serves as that planet's moon.
Film and television
- Star Trek (1966– ), a film, television, and print franchise originated by Gene Roddenberry. In some fictional reference works such as the Star Trek Spaceflight Chronology, Epsilon Eridani has been suggested as the possible star system of the planet Vulcan, the home planet of the Vulcan race, although James Blish had earlier proposed constellar associate 40 Eridani A as the Vulcan star system. The Star Trek canon later established Vulcan's distance as consistent with that of 40 Eridani, and the authorized (but non-canonical) Star Trek book Star Trek: Star Charts identifies it as such, while Epsilon Eridani was assigned a lesser role as the location of Axanar. The 40 Eridani location is furthermore attested by Roddenberry himself and in a statement by Commander Tucker in Star Trek: Enterprise that "Vulcan is 16 light years from Earth"—as is 40 Eridani A at 16.39 ly from the Sun (compared to Epsilon Eridani at ~10.5 ly).
- Babylon 5 (1994–1999), a space opera television series created by J. Michael Straczynski. This series, rife with prophecies, religious zealotry, racial tensions, social pressures and political rivalries, is centered on the eponymous Babylon 5 space station, a five-mile long O'Neill cylinder located in the Epsilon Eridani star system at the fifth Lagrangian point between the fictional planet Epsilon III and its moon (see graphic).
Other film and television
- Super Dimension Cavalry Southern Cross (1984), a Japanese anime series written by Jinzō Toriumi et al. and directed by Yasuo Hasegawa. The world of Glorie was selected for colonization after a catastrophic nuclear holocaust rendered the Earth uninhabitable. Similar to the home planet in size and atmospheric conditions, Glorie nonetheless presented a challenging natural environment: With little moderating ocean cover, and an eccentric elliptical orbit around Epsilon Eridani, it suffered severe winters and heavy glaciation during its aposiderions. With extensive terraforming, Glorie has been successfully adapted for terrestrial life, and it serves as the theater for extensive military adventures—both human and mecha.
- Space Precinct (1994–1995), a British television series created by Gerry Anderson. This combination of science fiction drama and police procedural is set in the year 2040 and features former NYPD detective Patrick Brogan, now a lieutenant with the Demeter City police force on the planet Altor in the Epsilon Eridani system. Brogan and his partner Jack Haldane must adjust to living in another solar system, and investigating crimes being committed by aliens as well as humans.
- Space: Above and Beyond (1995–1996), a television series created by Glen Morgan and James Wong. In early 2063, The Chigs declare war on humanity, launching what appears to be an unprovoked first-strike against the budding interstellar colonies of Vesta and Tellus. The colonies are destroyed and their few survivors taken prisoner. Vesta Colony, Earth's first extra-solar world, orbits Epsilon Eridani.
- Virtuality (2009), a television backdoor pilot created and written by Ronald D. Moore and Michael Taylor, and directed by Peter Berg. The story is set aboard the Phaeton, Earth's first starship, on a ten-year journey to explore the nearby Epsilon Eridani star system for a habitable refuge from its moribund homeworld. To pass the time, the crew immerses themselves in an advanced virtual reality system, which broadcasts their "adventures" to a worldwide audience back home. But all is not well: Crew members become ill, they initiate unstable romantic couplings, and the VR system itself begins to display bizarre—and dramatically interesting—malfunctions.
- "The Boyfriend Complexity" (2010), an episode of The Big Bang Theory, a situation comedy created by Chuck Lorre and Bill Prady, and directed by Mark Cendrowski. The series, embellished by wacky faux-scientific episode titles, concerns the eccentric doings of four hyperintelligent but socially inept scientists and their street-smart neighbor, a blonde waitress and aspiring actress. In this episode (S4:E9), Rajesh Koothrappali is remotely controlling a telescope in Hawaii, watching for varying luminosity as evidence of an extrasolar planet orbiting the star.
- BattleTech (1984), a wargame and related products launched by The FASA Corporation. Epsilon Eridani is one of the inhabited worlds closest to Terra. Originally a member of the Terran Hegemony, it passed into Capellan control after the collapse of the Star League. In subsequent years it changed hands multiple times as the result of various wars and treaties.
- 2300 AD (1986), a role-playing game designed by the Game Designers' Workshop. Dukou (Epsilon Eridani I), a habitable but glacier-bound world, is the location of the Manchurian semi-penal colony Xixiang. In the game, the Epsilon Eridani system is the main point of access to the Latin systems.
- Battlelords of the 23rd Century (1990–1998), a role-playing game designed by Lawrence R. Sims and published by Optimus Design Systems. There are many alien races in the Battlelords universe, but twelve are presented in the basic rulebook and form the basis for the Galactic Alliance. One of these is the race of Eridani Swordsaints, who inhabit the cold methane world Eridine in orbit around Epsilon Eridani.
- Frontier: Elite II (1993) and Frontier: First Encounters (1995), computer games written by David Braben et al.. The planets of the Epsilon Eridani system are dedicated to luxury-class and adult tourism, primarily directed towards the terraformed planet New California. The system does not fall under Federal laws, despite being deep in the core of the Federation. As a result, narcotics and slavery are both legal commodities in a thriving commercial market.
- Independence War (1997), a space combat computer game developed by Particle Systems and published by Infogrames. In the game, the player takes the role of a 23rd-century spaceship captain in the Earth Commonwealth Navy, commander of the Dreadnaught. The primary antagonists are rebellious insurgents called the Indies, a group distinguished by their elaborately and colourfully painted ships; it is the captain's job to bring them back under the control of Earth. The headquarters of the Indies lies somewhere in Epsilon Eridani.
- The Beast (2001), an influential early alternate reality game created by a team at Microsoft to promote the Steven Spielberg film A.I. Artificial Intelligence. Epsilon Eridani is the nexus of rogue space-faring AIs, and the birthplace of the advanced androids that appear at the end of the movie.
- Halo (2001– ), a video game franchise created by Bungie and published by Microsoft Studios. The planet Reach (Epsilon Eridani II) is a UNSC military stronghold, a shipyard, and the site of the SPARTAN-II super-soldier project which trained the series' role-protagonist John-117. The planet was glassed by Covenant forces from orbit and made largely uninhabitable in 2552, as a part of the enemy's final campaign to subdue the Earth. The game Halo: Reach is plotted around these events and the planet's eventual destruction (see Halo: The Fall of Reach, above). After the war with the Covenant, reterraforming efforts had begun by 2589.
- Race for the Galaxy (2007), a card game designed by Thomas Lehmann and published by Rio Grande Games. Players lay down cards representing worlds and economic development initiatives to build galactic civilizations. Epsilon Eridani is one of the start worlds in the base game, depicted as a dwarf planet orbiting the star inside the radius of one of the system's two asteroid belts.
- Face of Mankind (2009), a MMORPG designed by Marko Dieckmann and published by Nexeon Technologies. Players interact with each other in a freeform universe, comprising multiple locations spread across various planets. One of these is an ice planet orbiting Epsilon Eridani.
- Extrasolar (2014), an alternate reality web based game created by Lazy 8 Studios. Players control a rover exploring the surface of the third planet "Epsilon Prime" in the Epsilon Eridani system.
Epsilon Eridani is referred to as a location in space or the center of a planetary system unusually often in fiction. For a list containing many stars and planetary systems that have a less extensive list of references, see Stars and planetary systems in fiction.
Notes and references
- Clute, John; Nicholls, Peter (1993). "Big Dumb Objects". The Encyclopedia of Science Fiction. New York: St Martin’s Griffin. p. 118. ISBN 0-312-13486-X. BDOs normally turn out to be built by some mysterious vanished race of alien intellectual giants (in the case of Eon, by men from the future), with the dramatic function of leading their human discoverers to the brink of a conceptual breakthrough. Besides Bear's Eon, examples include Niven's Ringworld and Clarke's Rama.
- The association of a huge asteroid-sized mass of stone with an insubstantial wisp of fluff may at first blush seem like an oxymoron. Note however that, in terrestrial ecosystems, the biological function of bits of thistledown (see graphic) is to waft life-bearing seeds across gulfs of space and to deposit them in more or less hospitable remote locations where they might grow—quite similar to the original cosmic purpose of the Thistledown.
- Boyle, Alan (2009). The case for Pluto: How a Little Planet Made a Big Difference. Hoboken, NJ: John Wiley & Sons. p. 191. ISBN 0-470-50544-3.
- Guinan, Edward et al. (Aug 10, 2009). "The violent youth of solar proxies steer course of genesis of life". International Astronomical Union. Retrieved 2011-05-19.
- Janson, M et al. (September 2008), "A comprehensive examination of the ε Eridani system. Verification of a 4 micron narrow-band high-contrast imaging approach for planet searches", Astronomy and Astrophysics 488 (2): 771–780, arXiv:0807.0301, Bibcode:2008A&A...488..771J, doi:10.1051/0004-6361:200809984
- Schmitt, J H M M et al. (February 1996), "The extreme-ultraviolet spectrum of the nearby K Dwarf ε Eridani", The Astrophysical Journal 457: 882, Bibcode:1996ApJ...457..882S, doi:10.1086/176783
- Clute, John; Nicholls, Peter (1993). "Dickson, Gordon R". The Encyclopedia of Science Fiction. New York: St Martin’s Griffin. p. 332. ISBN 0-312-13486-X.
- Dickson, Gordon R (2002). Dorsai Spirit. New York: Tom Doherty Associates. pp. 18 ff, passim. ISBN 0-312-87761-7.
- Vinge, Vernor (2001). The Collected Stories of Vernor Vinge. New York: Tom Doherty Associates. p. 164. ISBN 0-312-87584-3.
- Clute, John; Nicholls, Peter (1993). "Barbet, Pierre". The Encyclopedia of Science Fiction. New York: St Martin’s Griffin. p. 90. ISBN 0-312-13486-X.
- Pournelle, Jerry (1978). "Singularity". Black Holes. Brooklyn NY: Fawcett Books Group. p. 242. ISBN 0-449-23962-4.
- Plait, Phil. "Fox TV and the Apollo Moon Hoax". Bad Astronomy. Retrieved 2012-03-01.
- Bear, Greg (1985). Eon. New York: Tom Doherty Associates. p. 427. ISBN 0-8125-2047-5.
- Clute, John; Nicholls, Peter (1993). "Forward, Robert L". The Encyclopedia of Science Fiction. New York: St Martin’s Griffin. p. 440. ISBN 0-312-13486-X.
- Tyers, Kathy (2004). Shivering World. New York: Bethany House Publishers. p. 49. ISBN 0-7642-2676-2.
- Clute, John; Nicholls, Peter (1993). "Turtledove, Harry". The Encyclopedia of Science Fiction. New York: St Martin’s Griffin. p. 1246. ISBN 0-312-13486-X.
- Weber, David (1998). Echoes of Honor. Riverdale, NY: Baen Publishing Enterprises. p. 464. ISBN 0-671-57833-2.
- Gould, Steven (1998). Helm. New York: Tom Doherty Associates. pp. 2 ff, passim. ISBN 0-8125-7135-5.
- Sawyer, Robert J (1998). Factoring Humanity. New York: Tom Doherty Associates. p. 303. ISBN 0-7653-0903-3.
- Reynolds, Alastair (2002). Revelation Space. New York: Ace Books. pp. 5, passim. ISBN 0-441-00942-5.
- Nylund, Eric (2001-10-30). "Interview with Eric Nylund, Author of Halo: The Fall of Reach". Halo.Bungie.Org. Retrieved 2012-02-28.
- "Epsilon Eridani". Halopedia. Retrieved 2012-02-28.
- Williams, Walter Jon (2008). Implied Spaces. San Francisco: Night Shade Books. pp. 293–294; 306. ISBN 978-1-59780-151-5.
- Mandel, Geoffrey (2002). Star Trek: Star Charts. New York: Pocket Books. ISBN 0-7434-3770-5.
- Baliunas, Sallie; Roddenberry, Gene et al. "Vulcan’s Sun". Retrieved 2012-03-02.
- Straczynski, J Michael (1995-10-08). "Babylon 5 Universe: The Station". Retrieved 2012-03-04.
- van Vliet, Wouter. "The Boyfriend Complexity, but nothing about what happened between Leonard and Penny!". ilikealot. Retrieved 2012-03-05.
- "The Beast". 42 Entertainment. Retrieved 2012-03-06.
- "What is Extrasolar". Lazy 8 Studios. Retrieved 2014-03-25.