Known Space is the fictional setting of about a dozen science fiction novels and several collections of short stories by American writer Larry Niven. It has also become a shared universe in the spin-off Man-Kzin Wars anthologies. The Internet Speculative Fiction Database (ISFDB) catalogs all works set in the fictional universe that includes Known Space under the series name Tales of Known Space, which was the title of a 1975 collection of Niven's short stories. The first-published work in the series, which was Niven's first published piece, was "The Coldest Place", in the December 1964 issue of If magazine, edited by Frederik Pohl. This was the first-published work in the 1975 collection.
The stories span approximately one thousand years of future history, from the first human explorations of the Solar System to the colonization of dozens of nearby systems. Late in the series, Known Space is an irregularly shaped "bubble" about 60 light-years across.
The epithet "Known Space" refers to a small region in the Milky Way galaxy, one centered on Earth. In the future that the series depicts, spanning roughly the third millennium, humans have explored this region and colonized many of its worlds. Contact has been made with other species, such as the two-headed Pierson's Puppeteers and the aggressive felinoid Kzinti. Stories in the Known Space series include events and places outside of the region called "Known Space" such as the Ringworld, the Pierson's Puppeteers' Fleet of Worlds and the Pak homeworld.
The Tales were originally conceived as two separate series, the Belter stories set roughly from 2000 to 2350 CE and the Neutron Star / Ringworld stories set in 2651 CE and later. The earlier, Belter period features solar-system colonization and slower-than-light travel with fusion-powered and Bussard ramjet ships. The later, Neutron Star, period features faster-than-light ships using "hyperdrive". Niven implicitly joined the two settings as a single fictional universe in the short story "A Relic of the Empire" (If, December 1966), by using background elements of the Slaver civilization from the Belter series as a plot element in the faster-than-light setting. In the late 1980s—having written almost no Tales of Known Space in more than a decade—Niven opened the 300-year gap in the Known Space timeline as a shared universe, and the stories of the Man-Kzin Wars volumes fill in that history, bridging the two settings.
Locations One aspect of the Known Space universe is that most of the early human colonies are on planets suboptimal for Homo sapiens. During the first phase of human interstellar colonization (i.e. before humanity acquired FTL), simple robotic probes were sent to nearby stars to assess their planets for habitation. The programming of these probes was flawed: they sent back a "good for colonization" message if they found a habitable point, rather than a habitable planet. Sleeper ships containing human colonists were sent to the indicated star systems. Too often, those colonists had to make the best of a bad situation.
Solar System Earth, the human homeworld, is ruled by the United Nations, a direct democracy, but not a utopia. An important organization is the ARM, a global police force tasked to deal with organlegging and crimes committed by cutting-edge technologies. For centuries, due to the perfection of organ transplant technology, all state executions were done in hospitals to provide organ transplants, and to maximize their availability nearly all crimes carried the death penalty, including such offenses as multiple traffic tickets or tax evasion. This period ended when Jack Brennan, who had consumed the Tree-of-Life root and become a human version of the Pak Protector, used his superior intelligence to engineer social change in medical technology and social attitudes that eventually reduced the use of organ banks to reasonable levels. Part of Brennan's manipulation was the development of a science known as "psychistry". Psychistry was used to "correct" all forms of "mental aberration" – the populace is extremely docile. To combat overpopulation (one estimate is 18 billion people), a license is required to procreate, only available after exhaustive testing has determined that a prospect is free of "abnormalities"; unlicensed procreation is a capital crime. This policy, in addition to the existence of the transfer booth and a one-world language and economy, has led to the populace eventually becoming fairly genetically homogeneous. To prevent the development of new WMDs, all scientific research is regulated by the government and potentially dangerous technology is suppressed. Due to such suppression, Earth has had fewer real breakthroughs in science than would be expected. A common title for people born on Earth is "Flatlander"; having been born and raised in the only environment in Known Space to which humans are well-adapted, they are considered naïve and a bit helpless by humans from colony worlds. The Moon is a separate entity, with its own distinct culture but is under the control of the same government as Earth. Humans native to the Moon are called "Lunies", and tend toward tall, lean body types regularly reaching eight feet in height. They are frequently referred to as looking much like Tolkien's Elves due to their physiques and alien allure. Mars, fourth planet in the Solar System and the first planetary colony in Known Space. Native "Martians" were exterminated by the Brennan genocide. No one goes there, as resources are easier to mine in the Belt and Jovian moons. Earth ultimately colonized Mars specifically to study the descent landing pod used by Phssthpok the Pak in 2124 AD and the research colony was still in existence in 2183 when the Martians were exterminated by Brennan. The colony expanded greatly during the first Man–Kzin war 2367–2433. The Sol Belt possesses an abundance of valuable ores, which are easily accessible due to the low to negligible gravity of the rocks containing them. Originally a harsh frontier under U.N. control, the Belt declared independence after creating Confinement Asteroid, a habitat with spin gravity that permitted safe gestation of children, and Farmer's Asteroid, the Belt's primary food source. Almost immediately a lively competition began between the fiercely independent "Belters" and the technology police of the U.N. Several years of tension and economic conflicts followed, but soon settled into a relatively peaceful trade relationship as the Belt has so many resources that the UN and the Earth need. Mercury is also a colony world with a small number of inhabitants, used mainly for mining and as a gravitational anchor for orbiting solar power stations which beam power to the more remote colonies using gigantic lasers. At the time of the First Man–Kzin War, human society is so pacifistic that no weapons exist; those who are able to even contemplate killing another sentient being or constructing a weapon for that purpose are regarded as mental aberrations and must take drugs to control their thoughts. However, an enormous laser, whether constructed as a weapon or not, makes a highly effective one, and it is strongly implied that the existence of the Mercury power satellites is a large part of what enabled Sol System to hold off the Kzinti in the early part of the war.
Other planets Down is the home world of the Grogs and a former Kzinti colony. It orbits "L5-1668",John Hewitt, et al., Larry Niven's Ringworld: Roleplaying Adventure Beneath the Great Arch, Chaosium Inc., 1984.The front cover illustration of Tales of Known Space: The Universe of Larry Niven, Del Rey, 1975 (at least 10 printings), has this as "L5-1665".This is almost certainly a corruption of BD+05 1668 (a.k.a. LHS 33), another name for Luyten's Star. a faint, cool M-type star, significantly redder and cooler than Sol and 12.3 light-years from it. Down is made habitable in part because of its large moon, Sheila. Grogs, though friendly, are feared by humanity, due to their telepathic ability to control the minds of animals (and possibly sentient species as well). Because of this fear, humans have placed a Bussard ramjet field generator in close orbit around Down's sun, thus enabling them to destroy the Grog population should they ever take hostile action against any sentient species. Jinx, orbiting Sirius A, is a massive moon of a gas giant (called Primary), stretched by tidal forces into an egg shape and tidally locked. It has habitable areas but has high surface gravity of 1.78 times Earth, near the limits of human extended tolerance. The points nearest to and farthest from Primary (called the "East" and "West" ends) lie elevated out of the atmosphere in vacuum. The atmosphere of the belt-region halfway between them is too dense and too hot to breathe, and is inhabited only by the Bandersnatchi. The zones between the vacuum areas and the high-density belt area have atmosphere breathable by humans. Jinx's "East" and "West" ends become a major in vacuo manufacturing area. Jinxian humans are short and squat, the strongest bipeds in Known Space. They tend to die early, from heart and circulatory problems. There is a tourist industry which provides substantial useful interplanetary trade credits for the Bandersnatchi, who allow themselves to be hunted by humans under strict protocols. Wunderland is a planet circling Alpha Centauri, and was the earliest extra-solar colony in Known Space's human history. It has a surface gravity of 60% that of Earth's and is hospitable to human life. Wunderland was invaded and its population enslaved by the Kzinti during the first Man–Kzin War. It was freed near the end of the First War by the human Hyperdrive Armada from We Made It. The system has an asteroid belt in the shape of a crescent, which gives it its namethe Serpent Swarm. The capital asteroid, Tiamat, houses one of the largest Kzin populations in Known Space. We Made It, orbiting Procyon A, got its name because the first colony ship crash-landed. Gravity is about three-fifths Earth's. The planet's axis is pointed along the plane of its ecliptic (like Uranus), creating ferocious winds on the order of during half of the planet's year, forcing the people to live underground. Natives are known as "Crashlanders", tend to be very tall, and many are albinos. Their capital, which was the site of their colony ship's landing, is called Crashlanding City. We Made It also has viscous, algae-choked "oceans" and a big icy moon, ironically named Desert Isle. Plateau in the Tau Ceti system is Venus-like, with a plateau (called Mount Lookitthat), half the size of California, rising high enough out of the dense atmosphere to be habitable. Inhabitants ("Mountaineers") are divided into two rigid hereditary castes, the "crew" and the "colonists", depending on whether their ancestors piloted the colonizing vessel. The crew are the upper caste, and hold power through their monopoly on organ transplantation and control of the police. The original colonists signed the "Covenant of Planetfall", agreeing that this outcome was just recompense for the labors of the crew during the voyage; that they signed at gunpoint as they were awakened from hibernation is kept secret from later generations, and also that those who refused, died. This repressive system is overthrown in A Gift From Earth, and the former inequality and caste system appears to have disappeared by the time The Ethics of Madness takes place.