In the background to the story in the book, an ancient and unseen alien race uses a device with the appearance of a large crystalline monolith to investigate worlds all across the galaxy and, if possible, to encourage the development of intelligent life. The book shows one such monolith appearing in ancient Africa, 3 million years B.C. (in the movie, 4 million years), where it inspires a starving group of hominids to develop tools. The ape-men use their tools to kill animals and eat meat, ending their starvation. They then use the tools to kill a leopard preying on them; the next day, the main ape character, Moon-Watcher, uses a club to kill the leader of a rival tribe. The book suggests that the monolith was instrumental in awakening intelligence.
The book then tells of the year C.E. 1999, detailing Dr. Heywood Floyd's travel to Clavius Base on the Moon. Upon his arrival, Floyd attends a meeting, where a lead scientist explains that they have found a magnetic disturbance in Tycho, one of the Moon's craters, designated Tycho Magnetic Anomaly One, or TMA-1. An excavation of the area has revealed a large black slab, precisely fashioned to a ratio of exactly 1:4:9, or 1²:2²:3², and therefore believed the work of intelligence. Floyd and a team of scientists travel across the Moon to view TMA-1, and arrive as sunlight falls upon it for the first time in three million years. It then sends a piercing radio transmission to one of the moons of Saturn, Japetus (Iapetus), where an expedition is then planned to investigate. One feature of the exposed monolith was that it absorbed all the sunlight cast on it. Therefore, no shadows were seen on its jet black surface.
The book then tells of the Discovery One mission to Saturn, whereof Dr. David Bowman and Dr. Francis Poole are the only conscious human beings aboard, while their three colleagues are in suspended animation, to be awakened near Saturn. The HAL 9000, an artificially intelligent computer, addressed as "Hal", maintains the ship. While Poole is receiving a birthday message from his family on Earth, Hal tells Bowman that the AE-35 communication unit of the ship is going to malfunction. Poole takes one of the extra-vehicular pods and swaps the AE-35 unit; but when Bowman conducts tests on the removed AE-35 unit, he determines that there was never anything wrong with it. Poole and Bowman become suspicious at Hal's refusal to admit that his diagnosis was mistaken; Hal then claims that the replacement AE-35 unit will fail. In communicating with Earth, Poole and Bowman are directed to disconnect Hal for analysis. These instructions are interrupted as the signal is broken, and Hal informs them that the AE-35 unit has malfunctioned.
As Poole is removing the unit he is killed when his spacesuit is torn, exposing him to the vacuum of space. Bowman, uncertain of Hal's role therein, decides to wake the other three astronauts, and therefore quarrels with Hal, with Hal refusing to obey his orders. Bowman threatens to disconnect him if his orders are not obeyed, and Hal relents. As Bowman begins to awaken his colleagues, he hears Hal open both airlocks into space, releasing the ship's internal atmosphere. From a sealed emergency shelter, Bowman gains a spacesuit and re-enters the ship, where he shuts down Hal's consciousness, leaving intact only his autonomic functions, and manually re-establishes contact with Earth. He then learns that his mission is to explore Iapetus, in the hope of contacting the society that buried the monolith on the Moon. Bowman learns that Hal had begun to feel guilty at keeping the purpose of the mission from him and Poole, against his stated mission of gathering information and reporting it fully; and when threatened with disconnection, he panicked and defended himself out of a belief that his very existence was at stake, having no concept of sleep.
Bowman spends months on the ship alone, slowly approaching Iapetus. During his approach, he gradually notices a small black spot on the surface of Iapetus, and later finds it identical in shape to TMA-1, only much larger. The scientists on Earth name this monolith "TMA-2", which Bowman identifies as a double misnomer because it is not in the Tycho crater and gives off no magnetic anomaly. When Bowman approaches the monolith, it opens and pulls in Bowman's pod. Before he vanishes, Mission Control hears him proclaim: "The thing's hollow — it goes on forever — and — oh my God! — it's full of stars!"
Bowman is transported via the monolith to an unknown star system, through a large interstellar switching station, and sees other species' spaceships going on other routes. Bowman is given a wide variety of sights, from the wreckage of ancient civilizations to what appear to be life-forms, living on the surfaces of a binary star system's planet. He is brought to what appears a pleasant hotel suite, carefully designed to make him feel at ease, and falls asleep, whereupon he becomes an immortal 'Star Child' that can live and travel in space. The Star Child then returns to Earth, where he detonates an orbiting nuclear warhead. This is not discussed again until the sequel to the book, 2010: Odyssey Two.Perils of technology
2001: A Space Odyssey explores technological advancement: its promise and its danger. The HAL 9000 computer puts forward the troubles that can crop up when man builds machines, the inner workings of which he does not fully comprehend and therefore cannot fully control.Perils of nuclear war
The book explores the perils related to the atomic age. In this novel, the Cold War is apparently still on, and at the end of the book one side has nuclear weapons above the earth on an orbital platform. To test its abilities, the Star Child detonates an orbiting warhead at the end of the novel, creating a false dawn below for the people on earth. Roger Ebert notes that Kubrick originally intended for the first spaceship seen in the film to be an orbiting bomb platform, but in the end he decided to leave the ship's meaning more ambiguous. Clarke, however, retained and clearly stated this fact in the novel.Evolution
The novel takes a panoramic overview of progress, human and otherwise. The story follows the growth of human civilization from primitive man-ape. Distinctively, Space Odyssey is concerned about not only the evolution that has led to the development of humanity, but also the evolution that humanity might undergo in the future. Hence, we follow Bowman as he is turned into a Star Child. The novel acknowledges that evolutionary theory entails that humanity is not the end, but only a step in the process. One way this process might continue, the book imagines, is that humans will learn to move to robot bodies and eventually rid themselves of a physical form altogether.Space exploration
When 2001: A Space Odyssey was written, mankind had not yet set foot on the moon. The space exploration programs in the United States and the Soviet Union were only in the early stages. Much room was left to imagine the future of the space program. Space Odyssey offers one such vision, offering a glimpse at what space exploration might one day become. Lengthy journeys, such as manned flights to Saturn, and advanced technologies, such as suspended animation, are described in the novel.Artificial intelligence
The book raises questions about consciousness, sentience, and human interactions with machines. Hal's helpful disposition contrasts with his malevolent behaviour. Through much of the movie he seems to have malfunctioned. At the end of the novel we learn that Hal's odd behaviour stems from an improper conflict in his orders. Having been instructed not to reveal the nature of the mission to his crew, he reasons that their presence is a threat to the mission, which is his prime concern. Hal's reversion to a childlike state as Dave shuts him down mirrors aspects of human death, and his expressed fear of being shut down causes Dave to hesitate.Accoutrements of space travel
The novel is deliberately written so as to give the reader an almost kinesthetic familiarity with the experience of space travel and the technologies encountered. Large sections of the novel are devoted to detailed descriptions of these. The novel discusses orbital mechanics and the manoeuvres associated with space travel with great scientific accuracy. The daily lives of Bowman and Poole on board the Discovery One are discussed in detail and give the impression of a busy yet mundane lifestyle with few surprises until the malfunction of Hal. Dr. Floyd's journey to Space Station One is depicted with awareness of fine points such as the experience of a Space Shuttle launch, the adhesive sauces used to keep food firmly in place on one's plate, and even the zero gravity toilet.
A sequel to the book, entitled 2010: Odyssey Two, was published in 1982 and adapted as a motion picture in 1984. Clarke went on to write two more sequel novels: 2061: Odyssey Three (1987) and 3001: The Final Odyssey (1997). To date, the last two novels have yet to be adapted as films.
James Blish commented that while Clarke's narrative provided essential elements of the story that Kubrick ignored or glossed over, "The novel has very little of the poetry of the picture" and "lacks most of the picture's strengths," but that "it has to be read before one can understand the picture."
Eliot Fremont-Smith reviewed the book positively in the New York Times, stating that it was "a fantasy by a master who is as deft at generating accelerating, almost painful suspense as he is knowledgeable and accurate (and fascinating) about the technical and human details of space flight and exploration."
Although the novel and film were developed simultaneously, the novel follows early drafts of the film, from which the final version of the film deviated. These changes were often for practical reasons relating to what could be filmed economically, and a few were due to differences of opinion between Kubrick and Clarke. The most notable differences are a change in the destination planet from Saturn to Jupiter, and the nature of the sequence of events leading to Hal's demise. Stylistic differences may be more important than content differences. Of lesser importance are the appearance of the monolith, the age of Hal, and the novel giving names to various spacecraft, prehistoric apes, and Hal's inventor.
Stylistically, the novel generally fleshes out and makes concrete many events left somewhat enigmatic in the film, as has been noted by many observers. Vincent LeBrutto has noted that the novel has "strong narrative structure" which fleshes out the story, while the film is a mainly visual experience where much remains "symbolic". Randy Rasmussen has noted that the personality of Heywood Floyd is different; in Clarke's novel, he finds space travel thrilling, acting almost as a "spokesman for Clarke," whereas in the film, he experiences space travel as "routine" and "tedious."
In the film, Discovery's mission is to Jupiter, not Saturn. Kubrick used Jupiter because he and special effects supervisor Douglas Trumbull could not decide on what they considered to be a convincing model of Saturn's rings for the film. Clarke went on to replace Saturn with Jupiter in the novel's sequel 2010: Odyssey Two. Trumbull later developed a more convincing image of Saturn for his own directorial debut Silent Running.
The general sequence of the showdown with Hal is different in the film from in the book. Hal's initial assertion that the AE-35 unit will fail comes in the film after an extended conversation with David Bowman about the odd and "melodramatic" "mysteries" and "secrecy" surrounding the mission, motivated because Hal is required to draw up and send to Earth a crew psychology report. In the novel it is during the birthday message to Frank Poole.
In the film, Bowman and Poole decide on their own to disconnect Hal in context of a plan to restore the allegedly failing antenna unit. If it does not fail, Hal will be shown to be malfunctioning. Hal discovers the plan by reading their lips through the EVA pod window. In Clarke's novel, ground control orders Bowman and Poole to disconnect Hal, should he prove to be malfunctioning a second time by predicting that the second unit is going to go bad.
However, in Clarke's novel, after Poole's death, Bowman tries waking up the other crew members, whereupon Hal opens both the internal and external airlock doors, suffocating these three and almost killing Bowman. The film has Bowman, after Poole's murder, go out to rescue him. Hal denies him reentry and kills the hibernating crew members by turning off their life-support. In the sequel 2010: Odyssey Two, however, the recounting of the Discovery One mission is changed to the film version.
The film is generally far more enigmatic about the reason for Hal's failure, while the novel spells out that Hal is caught up in an internal conflict because he is ordered to lie about the purpose of the mission.
Because of what photographed well, the appearance of the monolith that guided Moon-watcher and the other 'man-apes' at the beginning of the story was changed from novel to film. In the novel, this monolith is a transparent crystal; In the film, it is solid black. The TMA1 and TMA2 monoliths were unchanged.
While it is stated in the book that the ratio of the dimensions of the monolith are supposed to be 1:4:9, or the first 3 dimensions squared, the shape of the actual monolith seen in the movie does not conform to this ratio. 1:4:9 would produce an object that appears thick, wide, and squat. Kubrick wanted something taller and thinner, which he felt would be more imposing. Measurements taken from movie frames show that the movie monolith has dimensions approximately in the ratio 0.65:4:9 or 1:6:14.
In the book, Hal became operational on 12 January 1997, but in the movie the year is given as 1992. It has been thought that Kubrick wanted Hal to be the same age as a young bright child, nine years old.
The famous quote that opens the film sequel 2010: The Year We Make Contact – "My God—it's full of stars!" – is actually not in the 2001 film, although it is in the 2001 book.
The name of the Saturnian moon Iapetus is spelled Japetus in the book. This is an alternative rendering of the name, which derives from the fact that "consonantal I" often stands for "J" in the Latin language (see modern spelling of Latin).
In his exhaustive book on the film, The Making of Kubrick's 2001 (Signet Press, 1970, p. 290), author Jerome Agel discusses the point that Iapetus is the most common rendering of the name, according to many sources, including the Oxford English Dictionary. He goes on to say that "Clarke, the perfectionist", spells it Japetus. Agel then cites the dictionary that defines jape as, "To jest; to joke; to mock or make fun of." He then asks the reader, "Is Clarke trying to tell us something?"
Clarke himself directly addressed the spelling issue in chapter 19 of The Lost Worlds of 2001 (Signet, 1972, p. 127), explaining that he simply (and unconsciously) used the spelling he was familiar with from The Conquest of Space (1949) by Willy Ley and Chesley Bonestell, presuming that the "J" form is the German rendering of the Greek.1968, USA, New American Library (ISBN 0-453-00269-2), June 1968, hardback (First edition)
1968, USA, Signet, July 1968, paperback (First paperback edition)
1968, UK, Hutchinson (ISBN 0-09-089830-3), 1968, hardback (First British edition)
1968, UK, Arrow Books (ISBN 0-09-001530-4), October 1968, paperback
2000, UK, Orbit (ISBN 1-84149-055-5), December 2000, hardback (special edition)
2005, USA, Signet (ISBN 0-451-45273-9), July 2005, paperback
2013, BR, Aleph (ISBN 9788576571551), October 2013, brochure
The film 2010 was released in 1984 resulting in movie tie-in editions of both the 2001 and 2010 novels. At the time Signet Books reported that over 2.8 million copies of 2001 were in print and that 2010 was one of 1983's top sellers with 300,000 hardcover copies and 1.75 million first paperback editions printed.