Commercial Towing Vessel Nostromo, an M-Class starfreighter property of the Weyland-Yutani Corporation, is a tug, a towing vessel, hauling an enormous (some 1.5 miles in length) ore refinery and 20 million tons of raw ore, weighing many times the mass of the Nostromo. The ship itself is still substantial, over 60,000 metric tons and almost 245 metres (800 feet) long, including three decks, four holds, stores, engines, and lots of pipes and ducts; its escape ship is called Narcissus. The ship is fitted with a self-destruct system and separates itself from the ore refinery platform via an umibical detachment system. The interior features a large 'space jockey' cockpit for all crew piloting functions, a medical bay, dining area, central computer room, engineering areas, a hypersleep chamber and a labyrinthine network of connecting corridors.
(Many moviegoers have often mistaken the four-towered refinery as being the Nostromo itself and the Nostromo, when it detached itself from the refinery, as the shuttle Narcissus.)
The crew consists of seven people from various fields. In the order credited, they include Captain Dallas (Tom Skerritt), Warrant Officer Ripley (Sigourney Weaver), Navigator Lambert (Veronica Cartwright), Engineering Technician Brett (Harry Dean Stanton), Executive Officer Kane (John Hurt), Science Officer Ash (Ian Holm), and Chief Engineer Parker (Yaphet Kotto). There is also a tiger-striped orange tabby cat named Jones (often called "Jonesy" by the crew). The ship is equipped with a MU-TH-R 182 model 2.1 terabyte AI Mainframe (called "Mother" by the crew).
At the beginning of the first film, the ship is on a course returning to Earth from Thedus, using a form of FTL drive that requires the crew to spend most of the journey in "hypersleep" in order to conserve the ship's limited resources (food/water/air).
At the end of the film, Ellen Ripley destroys the Nostromo in an attempt to kill the xenomorph.
The design of the Nostromo is credited to illustrators Ron Cobb and Chris Foss. Ultimately Chris Foss' highly organic visions of the spacecraft were discarded in favor of Cobb's NASA-like utilitarian renderings. Ridley Scott made his own design contributions as well, adding most of the cathedralesque "refinery" portion, which dominates the craft on screen. Much of the ship's architecture, particularly its interiors and the colossal spires of its refinery structure, are inspired by the cavernous yet simultaneously claustrophobic sensibilities of haunted houses and castles from Gothic Horror films such as Nosferatu.
Right (middle image): Cobb's blueprint elevations of a late Nostromo (then named "Leviathan"), notation reads:
- Basic Lockheed CM 88B Bison transporter frame modified and fitted with a Yutani T7A NLS Stellar Drive. The original Saturn J3000 engines have been replaced by 2 Rolls Royce N66 Cyclone Thrust Tunnels with bi-polar vectoring for mid line life function. Each power plant developing 7,250,000 tons thrust (14,500,000,000 pounds) giving a high impulse total of 14,460,000 tons. 
Some of this information has filtered into the official canon, as appears below. The canon itself issues from the Aliens: Colonial Marines Technical Manual. The bottom of the Nostromo was built with pieces of Star Wars X-wings toy sets.
- ↑ The Book of Alien, Titan Books 1979