a model of the ship's head and a few body segments were used for close-up shots of Discovery docked with the Leonov. A 12-foot model was used for the primary motion control shots, while a smaller one was used to depict the Discovery tumbling end over end over Io. Fictional history Because of the lack of aerodynamic design and its immense size, Discovery One was assembled in and launched from orbit. As described in the novel, it was originally intended to survey the Jovian system, but its mission was changed to go to Saturn and investigate the destination of the signal from the black monolith found at the crater Tycho. As a result, the mission became a one-way trip to Saturn and its moon Japetus. (In the filmed telling, the destination remains Jupiter.) After investigating alien artifacts at Saturn and Iapetus, the preliminary plan is for all five members of the crew to enter suspended animation for an indefinite period of time. Eventually, it was intended that the much larger and more powerful Discovery Two (not yet completed) would travel to Japetus and return with everyone in hibernation. Ship features In the novel 2001: A Space Odyssey, Discovery One is described as being "almost 400feet long with a sphere 40feet dia." (122meters and 12.2meters respectively; the 2010 film mentions ) and powered by a nuclear plasma drive, separated by of tankage and structure, from the spherical part of the spaceship where the crew quarters, the computer, flight controls, small auxiliary craft, and instrumentation are located. The ship's carousel is a spinning band of deck, mounted inside the crew compartment, using centrifugal force to simulate the effects of gravity and is the primary living and work area. The three hibernating astronauts are also located here. The carousel provides Moon-level gravity rotating at just over 5rpm. The carousel can be stopped and the rotation stored in a flywheel. There is an automated kitchen (developed with the assistance of General Mills); a ship-to-Earth communications center; and a complete medical section where the astronauts undergo regular automated checkups. Areas outside the carousel, are micro-g environments where the crew members use Velcro shoes to attach themselves to the floor. Piloting, navigation, and other tasks take place in these areas. There is also a pod bay, where three one-man repair and inspection craft are kept, and the spaceship's primary HAL 9000 mainframe computer. Communications Discovery is