The same book famously featured a devastating inaccuracy: the eponymous Ringworld is not ( in ) a stable orbit and would crash into the sun without active stabilization.

When it was pointed out to Niven that the Ringworld was dynamically unstable, in that once the center of rotation drifted away from the central sun, gravity would pull the ring into contact with the star, he used this as a plot element in the sequel novel, The Ringworld Engineers.

* The Ringworld is an artificial world structure with three million times the surface area of Earth, built in the shape of a giant ring orbiting its sun, a million miles wide and with a diameter of 186 million miles.

One major problem was that the Ringworld, being a rigid structure, was not actually in orbit around the star it encircled and would eventually drift, resulting in the entire structure colliding with its sun and disintegrating.

The game is intended to be set on the Ringworld itself, an enormous single world discovered at the far reaches of Known Space, a ring around a sun at approximately the orbit of the Earth.

A major problem being that the Ringworld, being a rigid structure, was not actually in orbit around the star it encircled and would eventually drift, resulting in the entire structure colliding with its sun and disintegrating.

The fictional universe is also the home of species from outside Known Space, including the hominid inhabitants of a megastructure called Ringworld.

In Larry Niven's Ringworld novels, rishathra is " sexual practice outside one's own species but within the intelligent hominoids.

The Lying Bastard, the landing vessel in which Nessus, Louis Wu, Teela Brown and Speaker-to-Animals crash-land on the Ringworld, is based on a modified # 2 hull, specifically designed with most of the flight equipment and thrusters on the outside, to minimise the number of breaks in the hull, allowing a Slaver stasis field to be fitted to the inside of the ship, protecting the occupants from any danger ( by freezing them in stasis in the event of attack, for example ).

The Ringworld series is set in the Known Space universe.

The stories that constitute the Known Space series were originally conceived as two separate series: the Belter stories, featuring solar-system colonization and slower-than-light travel with fusion-powered and Bussard ramjet ships, and the Neutron Star / Ringworld series of stories, set much further into the future, which feature faster-than-light ships using " hyperdrive ".

At one time found on every Thrint estate throughout the Thrintun empire, the only known survivors in Known Space are on the planet Jinx, though they are later found on the Ringworld and on a forested planet called Beanstalk ( in the Man-Kzin Wars story " Hey Diddle Diddle ").

In the Known Space stories, Niven had created a number of technological devices ( GP hull, stasis field, Ringworld material ) which, combined with the " Teela Brown gene ", made it very difficult to construct engaging stories beyond a certain date — the combination of factors made it tricky to produce any kind of creditable threat / problem without complex contrivances.

Ringworld is a 1970 science fiction novel by Larry Niven, set in his Known Space universe and considered a classic of science fiction literature.

* The Incompleat Known Space Concordance — Appendix: The Ringworld

* Encyclopedia of Known Space: Ringworld

The players initially play explorers from Known Space, sent as scouts to the Ringworld.

Instead, the game and rules focused on parties of characters exploring the Ringworld itself, and, despite its vast size ( with a surface area larger than that of all of Known Space's inhabited planets put together ), many who bought the game felt limited by this one world setting.

" The article " The Dolphins of Known Space: A new race for the Ringworld Game " appeared in Dragon Magazine issue 95.

* The Ringworld Role-Playing Game: A Re-appraisal From Other Reviews on " Known Space: The Future Worlds of Larry Niven " fan site

Ringworld's Children is a 2004 science fiction novel by Larry Niven, the fourth in the Ringworld series set in the Known Space universe.

All the intelligent species of Known Space are interested in the Ringworld.

A number of previously revealed " facts " turn out to have been lies told by characters in the books, which is another common feature of Niven's Ringworld and other Known Space stories, especially those involving Protectors and Puppeteers.

According to the story in Ringworld ( expanded in the Known Space novel Juggler of Worlds ), the Puppeteers intervened with human reproduction beginning several generations in the past, with the intention of breeding humans for luck.

The Hot Needle of Inquiry which carried Chmeee, Louis Wu, and the Hindmost from Known Space to the Ringworld in The Ringworld Engineers also had a # 3 hull.

A # 4 GP hull is a transparent sphere around in diameter ; it is the largest ship size ever built in Known Space ( though Ringworld 1 refers to some STL " slowboat " colony ships as being larger and Louis Wu's internal monologue indicates the ship is more than a mile in diameter ).

There is some information on spaceships ( Human and City Builder ), hyperspace, a map of Human Space, and statistics for vehicles used on the Ringworld.

There have been many other wheel-shaped space habitats in science fiction, such as the Ringworld or the Earth-orbiting Space Station V invented by Arthur C. Clarke and Stanley Kubrick and depicted in Kubrick's 1968 movie 2001: A Space Odyssey.

His best-known work is Ringworld ( 1970 ), which received Hugo, Locus, Ditmar, and Nebula awards.

Niven's most famous contribution to the SF genre is his concept of the Ringworld, a band of approximately the same diameter as Earth's orbit rotating around a star.

It is one of the most visible influences of the Ringworld concept on popular culture.

In Ringworld it is revealed that this was in part due to clandestine meddling by the Pierson's Puppeteers.

No description is given, but the Ringworld RPG suggests they resemble horned birds and that their homeworld has low gravity.

When the Protectors reappear in The Ringworld Engineers and its sequels, it is strongly indicated that they constructed the Ringworld.

Likewise, every hominid species found on the Ringworld is descended from Pak breeders, and all are susceptible to the virus of Tree-of-life.

In the Ringworld era it is still a frontier world, and is home to enormous birds the inhabitants have dubbed " rocs ".

* Silvereyes is, at the time of Ringworld, the furthest Human world from Earth ( 21. 3 light-years, 60 days at Quantum-I hyperdrive speeds ), orbiting Beta Hydri.

In Niven's novel Ringworld's Children the Ringworld itself is converted into a gigantic Quantum II hyperdrive and launched into hyperspace while within its star's gravity well.

Ringworld's Children reveals that there is life in hyperspace around gravity wells and that hyperspace predators eat spaceships which appear in hyperspace close to large masses, thus explaining why a structure as large as the Ringworld can safely engage the hyperdrive in a star's gravity well.

In Ringworld's Children, it is suggested boosterspice may actually be adapted from Tree-of-Life, without the symbiotic virus that enabled hominids to metamorphose from Pak Breeder stage to Pak Protector stage ( mutated Pak breeders were the ancestors of both Homo sapiens and the hominids of the Ringworld ).

On the Ringworld, there is an analogous ( and apparently more potent ) compound developed from Tree-of-Life, but they are mutually incompatible ; in The Ringworld Engineers, Louis Wu learns that the character Halrloprillalar died when in ARM custody after leaving the Ringworld, as a result of having taken boosterspice after having used the Ringworld equivalent.

They were invented by the Pierson's Puppeteers, and their existence is not generally known to other races until the events of The Ringworld Engineers.