Asimov notes in "
The Psychohistorians" that there are "nearly twenty-five million inhabited planets in the Galaxy". ; 61 Cygni : A star system advanced by
Lord Dorwin as the potential site for a planet of origin for the human species. Lord Dorwin cites 'Sol' (meaning Earth's Sun) and three other planetary systems in the Sirius Sector, along with Arcturus in the Arcturus Sector, as potential original worlds. Claims were made as early as 1942 that 61 Cygni had a planetary system, though, to date, none have been verified. ; Achilles : A gas giant planet in the Anacreon system. Its size is somewhere between
Saturn and
Neptune, about 1.7 times as dense as water, with a strong equatorial bulge. In appearance, it is a dark, yellow-biased red, with scattered orange patches indicating storm systems. Achilles has several moons, such as one within the orbit of Neoptolemus, four between that and Ulysses, and twenty outside of Ulysses; all of these others are captured asteroids. ; Alpha : It orbits the star Alpha Centauri A (only 4.2
light-years from Sol). The Empire
terraformed this planet to hold Earth's inhabitants after it was devastated by radiation, but the project was never completed. Covered almost entirely with water, save for a fifteen-thousand-square-kilometer island, this planet was considered by Lord Dorwin to be the original system of humanity. The inhabitants call it New Earth and live a simple lifestyle that of women and men are completely shirtless, weather permitting, and the men engage in long sea voyages to fish. About halfway into the thousand-year darkness after the fall of the Empire,
Golan Trevize ventured to this planet in his search for Earth. The inhabitants seemed nice enough but tried to infect him and his crew with a disease. After leaving, Trevize headed to the Solar System. ; (also known as Anacreon A II) : A planet near the outer end of the periphery. As part of the Galactic Empire was the capital of Anacreon subprefecture, Anacreon prefecture, and Anacreon Province, and later the Anacreon Kingdom. Anacreon is a
binary star system. The pair orbit at 73.8 AU with a period of, in Earth terms, 181 years, 84 days and 14 hours. ; Arcturus : One of the major planets. It is the capital world of the Sirius Sector in the Galactic Empire. It seems to have been named for the star
Arcturus in
Boötes. ; : Originally named New Earth, in later millennia the planet would be renamed "Aurora", which means "dawn", to signify the dawning of a new age for the Spacer culture. It is an Earthlike planet, the innermost planet orbiting the star
Tau Ceti (12 ly from Sol). It was the first Spacer planet colonized, established in 2065. Its capital is Eon (about 20,000 inhabitants). As it was highly populated and developed, it was considered the "capital" of the Spacers. The planet has two moons: Tithonus I and Tithonus II. Aurora at its height had a population of 200 million humans, and 10 billion robots. The head of its planetary government was called the "Chairman". The largest city on the planet was Eos (which means also "dawn"), the administrative and robotic centre of Aurora, where Han Fastolfe and Gladia Solaria lived. The University of Eos and the Auroran Robotics Institute were both located within Eos. After the decline of the Spacers, the planet's remaining inhabitants are believed to have emigrated to Trantor, settling in the Mycogen Sector. The descendants of the Aurorans, or Mycogenians, never forgot Aurora, but they apparently evolved to the point where they were indistinguishable from Settlers. The scripture of the Mycogenians mentions Aurora, robots, and other topics;
Hari Seldon peruses this document and finds the "corpse" of a robot in Mycogen also. Ironically, the culture of Mycogen appears to be in many ways a complete opposite of Aurora. Where the society of Aurora had complete gender equality and social mobility, Mycogen has a restrictive caste system with women apparently taking the place of Auroran robots, with absolutely no rights. It is also very restrictive sexually, where Aurora was basically a free love society. Mycogen, a sector of Trantor, identifies Aurora as the first planet and gives a high value to the Robots, lamenting his loss. The searchers for Earth visit Aurora, along with other ancient settlements. The planet is by then not inhabited by human beings, and its desertified ecology is dominated by feral dogs. ; Comporellon (originally Baleyworld) : A planet located near Gaia and Sayshell, Comporellon was renowned for its particularly old age. It was founded by the second wave of space colonists, known as the Settlers, and thus had a very superstitious attitude toward the first wave, the Spacers. They were also superstitious about Earth. Golan Trevize,
Janov Pelorat, and Bliss visit Comporellon in
Foundation and Earth, and acquire the coordinates of three Spacer worlds: Solaria, Aurora, and
Melpomenia from a historian. Comporellon was under the political influence of the First Foundation, but its awkward situation caused resentment toward Foundationers. Its inhabitants preferred clothes that were white, gray, and black. Trevize comments that their food could be very good. Astronomically, Comporellon was a very cold ice world. ; Earth (sometimes called Old Earth, Gaia or Terra) : A planet, the most common setting of his robot short stories. Earth is the planet upon which humans have lived for longer than anyone remembers. Earth features in one of several Origin Myths found throughout the Galactic Empire. Its history, however, is shrouded in the mists of time. Earth was the third planet from its sun (called Sol) and had one large moon (Luna). From millions of years BC to the early Galactic Era, Earth was one of the most, if not the most, important planets in the galaxy, being one of the only planets to ever develop life without being colonized by other worlds, and being the origin planet of the human race, who would go on to dominate the galaxy through the Galactic Empire. Around 65,000,000 BC, the
dinosaurs, the original dominant race of Earth, were killed by a race of small intelligent lizards armed with guns, which either left Earth or died out. Eventually, humans evolved on the planet. Up until the 20th century AD, the human race progressed, having wars and developing technology, experiencing the ups and downs of civilization, but nothing extremely radical happened, and, most importantly, no one made an attempt to leave Earth and colonize new worlds. In the early 20th century, two world wars were endured, WW1 in the 1910s and WW2 in the 1940s. Eventually, in 1973, the human race reached for the moon. The Prometheus failed, but, after some complicated series of events, the New Prometheus reached the moon in 1978, achieving the goal of leaving Earth, if only slightly. From around 1979 to 1982, WW3 took place, ending nationalism, and splitting Earth into Regions. From there, the planet experienced a new renaissance, developing
positronic brains in the 1980s and 1990s, governed by the
Three Laws of Robotics. One of the most important early pioneers in robotics was
Susan Calvin (1982-2064), who was the first and chief
robopsychologist at
US Robots and Mechanical Men from 2007 to 2058. Robots eventually grew very advanced. In 2065, Earth colonized the first extrasolar world, Aurora, the World of the Dawn. This was the first of the great Spacer Worlds, which were colonized over thousands of years across the stars. Around 3720, they rebelled against Earth, winning the Three-Week War, and would become higher in society than Earth. In 4724, detective
Elijah Baley managed to allow the colonization of new worlds by Earth, which had been suppressed, and the Settler worlds were made. These were threatened in 4922 but were saved due to the efforts of
Gladia Solaria,
R. Daneel Olivaw and
R. Giskard Reventlov, at the cost of Earth being made radioactive by
Levular Mandamus. Eventually, the Settler worlds spread across the galaxy, outnumbering the Spacer worlds greatly, and Earth sank into unimportance, but was still known of and not looked down on. 1,000 years into the radioactivity, it was believed to be the result of a nuclear war. Thousands of years later, in the year 500 of the Foundation Era, Daneel Olivaw was on the Moon of Earth and encountered Golan Trevize. ; Fomalhaut : A star mentioned in novel
Pebble in the Sky. Joseph Schwartz of Chicago is transported by a stray beam of radiation to the Earth of the far future, which is part of a galactic empire ruled by the planet Trantor. Finding himself in wild countryside, he searches far and wide for help until he stumbles upon a cottage — only he can't understand the dwellers, nor they, him. One of them theorizes, "He must come from some far-off corner of the Galaxy ... They say the men of Fomalhaut have to learn practically a new language to be understood at the Emperor's court on Trantor." Asimov would later substantially abandon using any real star names at all in the empire. ; : Whose people are known by the same name or the Anti-Mules, is a planet described in the novel ''
Foundation's Edge and referred to in Foundation and Earth''. The name is derived from the
Gaia hypothesis, which is itself eponymous to
Gaia, the
Earth goddess. Gaia is located in the Sayshell Sector, about ten parsecs (32 light-years) from the system Sayshell itself. It orbits a G-4 class star and has one natural satellite (50 km or 31 miles in diameter). Its axial inclination is 12°, and a Gaian day lasts 0.92 Galactic Standard Days. In its course of settlement, the human beings on Gaia, under robotic guidance, not only evolved their ability to form an ongoing group consciousness but also extended this consciousness to the fauna and flora of the planet itself, even including inanimate matter. As a result, the entire planet became a super-organism. Gaia was founded by R. Daneel Olivaw during the Empire's reign. Even then, the galaxy left it alone and it evaded taxes. By 498 F.E., Gaia had a population of one billion, a high population for a planet at that time. The inhabitants hoped eventually to create a complex ecology; all human-settled planets in the Galaxy —except Earth— had simple ecologies. The inhabitants of Gaia were all tied together into a telepathic group consciousness when it was founded; this consciousness was eventually extended to the non-human life, and later to the inorganic material of the planet. This would explain the
Mule's incredible psychic powers, as Gaia was said to be his home planet. ; Gamma Andromeda : A star system mentioned in the novel
Foundation. A catastrophic nuclear reactor meltdown occurred on Gamma Andromeda V in the year 50 F.E. The meltdown killed several million people and destroyed at least half the planet. ; Jennisek : A planet in close vicinity of Helicon, its traditional rival. This planet was described by Hari Seldon in
Prelude to Foundation. ; : A planet located in the Periphery, Kalgan was a world of no particular resource or strategic value which rose to prominence during the reign of the Galactic Empire as a pleasure planet. Imperial nobles would visit Kalgan as a means to indulge themselves, making the planet and its leadership immensely prosperous. Because of its ability to stay neutral from conflict and to provide tourism as its main amenity, Kalgan survived the decline of the Empire with ease and eventually came under the control of a warlord. In 310 F.E., the Mule, as chronicled in
Foundation and Empire, took over Kalgan by converting its warlord into his mind-slave. For a brief time, over a third of the Galaxy was ruled from Kalgan through the Mule's Union of Worlds, but after his death, the Lords of Kalgan were unable to maintain this level of control. The Union disintegrated into a mere 27 worlds and was almost completely encapsulated by the economic and political control of the Foundation. In 376 F.E., Lord Stettin, urged by his own egomania, decided to invade the Foundation. For a brief time, the power of Kalgan was extended, before the morale boost of the
Seldon Plan caught up to Kalganians fighting on the front. Demoralized, they were easily overcome by the brilliant technical maneuvers of the Foundationer Navy. The peace deals following the Stettinian War made the subject worlds of Kalgan autonomous and, through popular vote, they were permitted to become independent or to join the Foundation Federation. After this crushing defeat, Kalgan ceased to play a major role in galactic history. ; : A planet in the novel
Foundation. Located in the Whassalian Rift, it was the capital of the Republic of Korell. Korell was one of those frequent phenomena of a republic only in name. The dictator, called the Commdor 'first citizen of the state', is elected every year. Through some twist or another, a member of the Argo family is always chosen. According to
Hober Mallow, people who didn't like this arrangement had "things" happen to them. Unlike a de jure monarch, the de facto monarchy associated with the status of the Commdor was not moderated by the typical influences of "honour" and "court etiquette". Korell was the third
Seldon Crisis because it was the first nation encountered by the Foundation with an effective system of nucleics. Hober Mallow was sent to investigate. Mallow visited Asper Argo, Commdor of Korell, and opened up trade with his people through him. Despite discovering the steel foundries were not nuclear, Mallow did spot nuclear blasters provided by the Galactic Empire. Otherwise, Korell was decadent. The only remains of the Empire were 'silent memorials' and 'broken buildings'; the navy consisted of 'tiny, limping relics' and 'battered, clumsy hulks'. Mallow later learned that the viceroy of the Normannic Sector was providing Korell with nuclear blasters and with ships (five by the time Korell declared war with the Foundation; a sixth was promised). Mallow quickly realised that the real enemy was the Empire, not Korell; forcing himself into the office of mayor, Mallow was able to destroy the threat of Korell by doing nothing. Since his visit three years before had made Korell dependent on Foundation-made goods, the Korellians raised a good deal of complaints about their minor inconveniences. Since there was no threat of foreign conquest, the people became rebellious. Faced with this situation, the Commdor was forced to surrender to the Foundation unconditionally. The planets of the Korellian Republic eventually entered the Foundation's hands. They were captured briefly by Kalgan during the early stages of the war with Kalgan. ; Melpomenia : A planet in the novel
Foundation and Earth and it was one of the fifty Spacer worlds, colonized by the first wave of settlers from Earth. It was nineteenth in the order of settlement. In their search for the planet of origin of the human species, the third set of coordinates given to Golan Trevize, Janov Pelorat, and Bliss points to Melpomenia, an old, dead Spacer world with a very thin atmosphere and almost no signs of civilization except for some old ruins. One of these ruins was found to be the "Hall of the Worlds", within which was a wall inscribed with the names, coordinates, and dates of the settlement of all the fifty Spacer worlds in chronological order. This information is later used by Janov Pelorat to deduce the approximate position of Earth in the galaxy. The first try led Pelorat not to Earth but to the nearby planet Alpha (in the system of Alpha Centauri, approximately four light-years away from Earth). In addition, they also happen to find that even in this harsh, nearly air-less world, life does manage to survive in the form of a kind of moss that lives on the faintest traces of carbon dioxide. The moss starts to grow along the edges of the face-plates of their spacesuits, and Trevize realizes that if it were to somehow get within their ship, the
Far Star, it would become impossible to control. It would follow the trail of carbon dioxide along their nostrils and into their lungs and kill them. Using his blaster on minimum power, he burns away the moss on their spacesuits and also along the
Far Star's airlock so that they can get inside safely. ; (originally named Delicass) : Was a small agricultural planet located near the center of the galaxy, near Trantor. After the Great Sack, it was the location of the last seat of the Galactic Empire.
Dagobert IX short reign stemmed from Neotrantor. In
Foundation and Empire,
Toran and Bayta Darell,
Ebling Mis, and the Mule visit Neotrantor during their search for the Second Foundation. They are given permission by Dagobert IX to enter the Imperial Library on Trantor but are stopped by
Dagobert X, who wishes to marry Bayta. After the Mule kills the crown prince, the group leaves the disenfranchised Neotrantor. ; Nishaya : A planet mentioned in the novel
Forward the Foundation. Part of the pre-Imperial Kingdom of Trantor. At the end of the Empire, the planet was noted for its goat herding and high-quality cheeses. Laskin Joranum pretended to be from Nishaya during his campaign to overthrow
Eto Demerzel. His identity was compromised when Hari Seldon noted that he had a perfect fluency of the Trantorian dialect and was opposed to native Nishayans who spoke a very different dialect of Galactic standard. ; Santanni : A planet 9000 parsecs (29,000 light-years) from Trantor and 800 parsecs (2600 light-years) from Locris. In 12,058 G.E. the population of Santanni attempted to rebel against the Galactic Empire.
Raych Seldon, son of psychohistorian Hari Seldon, was killed in the rebellion, valiantly defending the University of Santanni. After the founding of the Foundation, Santanni traded with it until the trade route was cut off by the rebellion of Anacreon. One known thing of Santanni make was the cigar box possessed by
Jord Fara, and later by
Salvor Hardin. It was captured in the early stages of the war with Kalgan. After the death of the Mule, Santanni was instrumental in breaking the siege on Terminus levied by the Mule's successor,
Han Pritcher in 308 F.E. ; Sayshell : Was a planet in the Periphery. It was the capital of the Sayshell Union, which was renowned for having resisted the control of the Foundation Federation for several hundred years during the Interregnum, despite being completely surrounded by Federation territory. Sayshell features heavily in ''Foundation's Edge''. According to the legends of Sayshell, the planet was founded by a group of colonists who were not known to hail from any other colonized world, leading some historians, such as Janov Pelorat, to conclude that Sayshell was a colony founded directly from Earth. The Sayshellians themselves believed (incorrectly) that Earth was located somewhere within Sayshell Sector. Due to the protection of the mentalic planet Gaia, Sayshell was never truly threatened by outside forces for all of its history. Under the Galactic Empire, Sayshell received minimal taxation and enjoyed a large degree of independence from Imperial controls. Later, after the fall of the Empire, Sayshell remained untouched by the anarchic war which consumed most of the Galaxy and eventually from the control of the Mule's Union of Worlds and the Foundation Federation. Sayshell was briefly threatened by the Foundation Federation under Harla Branno, who in reality wished to destroy the planet Gaia (which lay completely within Sayshellian territory). However, Gaia used her mentalic influence to convince the Sayshellians that, in the end, Mayor Branno was looking for a neutrality-trade treaty, marking the end of Sayshell's brief stint in galactic affairs. Sayshellian culture was noticeably different from that of the ultra-scientific Foundation Federation. It stressed mysticism (especially the influence of dreams) and the respect of nature, as evidenced by the percentage of Sayshellian wildlife that was still preserved from human influence. Sayshellians also had excellent cuisine, and a minor dislike toward outsiders, especially Foundationers. The religion and philosophy of Sayshell seem to be modeled on
Buddhism. ; : A planet prominent in
Foundation and
Foundation and Empire. It was the capital of the Normannic Sector of the Galactic Empire, and once one of its richest planets. Shortly after 100 F.E., Wiscard, the viceroy of Siwenna, rebelled. Most of the subjects remained loyal to the Empire and overthrew Wiscard, led by Patrician
Onum Barr. The Imperial Admiral dispatched to Siwenna was angered at this, because it robbed him of his glory. So, he put most of the population of Siwenna under the atom blast, charging them with the crime of rebelling against an Imperial viceroy (Wiscard). Much of its population was killed, and Barr himself lost five sons and a daughter; only his sixth son,
Ducem Barr, survived. Because of the rampant destruction of Siwenna, the Admiral set himself up as viceroy but moved the capital of the Normannic Sector to Orsha II. Between this time and its conquest by Bel Riose in 200 F.E., Siwenna rebelled five times, eventually becoming independent. When the campaign led by Riose against the Foundation ended, the Siwenna province transferred to the Foundation, the first Imperial province to pass directly from the Empire to the Foundation. After the beginning of the Foundation Era, Siwenna began to run downhill. 'The physical resources of twenty-five first rank planets take a long time to use up. Compared to the wealth of the last century, though, we have gone a long way downhill—and there is no sign of turning, not yet,' –Onum Barr, to Hober Mallow, 150 F.E. About 50 years before,
Stanel VI died, ending a reign under which Siwenna came close to achieving its ancient prosperity. Little is known of Siwennian culture, except that when Riose first met Ducem Barr, it was 'socially impossible not to drink tea on Siwenna'. ; Smyrno : A planet located in the Anacreon Province. It is originally a prefect but later becomes one of the Four Kingdoms in the Anacreon Province that broke away from the Galactic Empire c. 50 F.E. The kingdom of Smyrno has no nuclear power until the Foundation arrives. The planet itself is located a little less than 50 parsecs (163 light-years) from Terminus. Its name is a parallel with
Smyrna, an important city of the
Roman Empire in
Anatolia. Smyrno is hot and dry, the rooms smell of sulphur, and people live underground. Its most famous citizen is Hober Mallow, one of the major characters from the Foundation series. Its citizens are often discriminated against by Foundation members. Smyrnians are often seen as unintelligent and untrustworthy. Jorane Sutt, a political enemy, to Mallow, who eventually becomes mayor, uses Mallow's ethnicity against him. ; : A planet in
Robot and
Foundation series. Inhabited by Spacer descendants, Solaria is the fiftieth and last Spacer world settled in the first wave of interstellar settlement. It was occupied from approximately 4627 AD by inhabitants of the neighboring world Nexon, originally for summer homes. It was ruled by a Regent after it became independent around roughly 4727 AD. It had perhaps the most eccentric culture of all of them. The Solarians specialized in the construction of robots, which they exported to the other Spacer Worlds. Solarian robots were noted for their variety and excellence. They also exported their grain, which was used to make a pastry known as the pachinka. Originally, there were about 20,000 people living in vast estates individually or as married couples. There were thousands of robots for every Solarian. Almost all of the work and manufacturing was conducted by robots. The population was kept stable through strict birth and immigration controls. In the era of
Robots and Empire, no more than five thousand Solarians were known to remain. Twenty thousand years later, the population was twelve hundred, with just one human per estate. Solarians hated physical contact with others and only communicated with each other via holograms. A few hundred years after Elijah Baley's visit to the planet, Solarians retreated from the Galactic scene and fled underground. The Solarians genetically altered themselves to be hermaphroditic and have the ability to use telekinesis. They specially made robots that were made to kill any foreigners who came to the planet. In 499 F.E. (approximately 25,066 AD), Solaria was visited by Golan Trevize, Janov Pelorat, and Bliss. They landed on the estate of Sarton Bander, the "Ruler" of a Solarian estate (note that Sarton was the last name of R. Daneel Olivaw's designer, Roj Nemennuh Sarton of Aurora). They learned of the sociological developments of Solaria through Bander, who apparently took a secret pleasure in having something close to intellectual companionship, or at least an intellectual audience. To prevent them from providing information to the Galaxy about Solaria and in keeping with Solarian customs and beliefs, not to mention preventing other Solarians' discovery of shameful personal contact with offworlders, Bander attempted to kill the visitors but was instead killed in self-defense by Bliss, resulting in the shutdown of all of the robots and other machinery of the Bander Estate. The visitors were able to escape, but not before discovering a child in one of the countless rooms of the estate,
Fallom, assuming it to be a successor to Bander (who had not mentioned the existence of an heir, but had mentioned that there would be one at the appropriate time or in the case of an unforeseen accident), whom they would ultimately bring with them to Earth. Had they left Fallom on Solaria, the child would almost certainly have been killed, because it was seen as a surplus child and also had not as yet developed its transducer lobes, therefore not counting as a Solarian and being expendable. Fallom demonstrated great precocity in learning Galactic and would eventually stay on the Moon of Earth to mentally merge with Daneel Olivaw. == Selected awards ==