The Terok Nor type of space stations were unusual by Federation standards, classified by Starfleet as a "hybrid planar-columnar triradial structure". Its basic form consisted of a central core assembly containing most primary systems, connected by crossover bridges to a series of two concentric rings for habitat and docking facilities, and a series of three sweeping pylons containing ore-processing and additional docking facilities. The station had at least five transporter rooms. (DS9: "Things Past")
In 2369, Kira Nerys suggested that the Klaestrons must be allies with the Cardassians because they knew about the station layout of Deep Space 9 and must have received that information from them. (DS9: "Dax")
The central core was a roughly cylindrical structure consisting of several terraced platforms containing various key facilities. At the extreme dorsal end of the core was the operations center and the subspace communications antennae, as well as the deflector shield generators. Below this assembly was the three-level Promenade, a public area for commerce and recreation. The Promenade on Deep Space 9 housed the station's infirmary, the security office, the Bajoran temple, and Quark's. The station also featured a wardroom which was used in a similar fashion to a briefing room on Starfleet vessels, though its large area allowed it to be used for a variety of other purposes.
The lower sections of the core contained engineering and support facilities, including at least one large industrial replicator, the computer core, and multiple deuterium fuel tanks. At the extreme ventral end sat the six fusion reactors.
The command level was part of the central core of the Terok Nor type. It was the primary operations center for the station, and contained primary access to all major operations of the station including science, tactical, and flight control. It also contained the office of the commanding officer.
In 2369, when Chief Miles O'Brien repaired the replicators on the command level but not the malfunctioning replicators at Quark's, Quark tried to gain access to the station layout to display all repaired replicators, but this information was restricted to security clearance five and above. Quark was able to use two isolinear rods to display the information and bypass the security code, acquiring the locations of the repaired replicators. (DS9: "Babel")
The habitat ring was the inner ring of the station's structure, intended primarily for the housing of most of the station's semi-permanent residents. Spaced along the ring were also six landing pads, used by Starfleet's runabouts and other small craft. The station itself could accommodate seven thousand people; Deep Space 9 only housed three hundred in 2369. (DS9: "Captive Pursuit")
Also mounted along the habitat ring were three large protrusions, upon which a large portion of the station's armaments were mounted, as well as its tractor beams.
The guest quarters of the visiting Federation ambassadors Taxco, Vadosia, and Lojal were located in Corridor H-12-A in the habitat ring. The ambassadors, guided by Doctor Julian Bashir, experienced a plasma surge, caused by overloading the station's computer in 2369. (DS9: "The Forsaken")
The docking ring was the outer ring of the station's structure, and was used primarily for moving and storing goods and for starship docking facilities. Twelve large docking ports were distributed around the perimeter, and numerous cargo bays were connected to these facilities. In addition, a series of six thrusters were mounted on the edge of the ring. These thrusters were intended mainly for maintaining orbital position.
Six large, sweeping docking pylons emerged from the docking ring; three from the dorsal and three from the ventral surfaces of the docking ring to give DS9 its characteristic spindly shape. At the extreme end of each pylon was an additional docking port (for a total of six on the pylons), which could accommodate larger starships up to those approximately the size of a Galaxy-class. The majority of the pylons' internal structure was used up by ore processing facilities.
A51 was a restricted area aboard Deep Space 9 that housed the station's deflector array controls and several EPS conduits. Rom opened a service hatch labeled "A51 | Restricted Area | Authorized Personnel Only" when attempting to disable the deflector array before the Dominion could fire an antigraviton pulse at the self-replicating minefield that was preventing Dominion ships from coming through the wormhole. (DS9: "Behind the Lines")
Designing the station (exterior)
The task of designing the space station Deep Space 9 – which had to be a new, iconic and alien-looking image that could be quickly recognized when seen on a small television screen – was a long, involved process that took several different directions before evolving into the final design we now take for granted.
Production designer Herman Zimmerman was the man assigned to come up with this fresh and unique look that would be the centerpiece of the next Star Trek show to follow Star Trek: The Next Generation. Zimmerman was given three months in which to design the station, a huge amount of time in comparative terms insofar as the normal amount of time to design something like this for a TV show is about two to three weeks.
According to Mike Okuda, one of the first things that the producers said to him about the basic design of the station was that "they wanted it not to look Starfleet, they wanted it to look weird." (Deep Space Nine: A Bold Beginning, DS9 Season 1 DVD special features)
One of the earliest ideas for the station was that it was to be a Tower of Babel-type structure which had been built up by many different cultures over many centuries, all using different technology, and that each part of the station was to have a different layout to every other part.
The final design was arrived at when Rick Berman saw a gyroscope-type design by Zimmerman, and suggested "breaking" the hoops at the top and bottom.
The physical model of Deep Space 9 was designed by Herman Zimmerman and Rick Sternbach. Contributing artists included Ricardo Delgado, Joseph Hodges, Nathan Crowley, Jim Martin, Rob Legato, Gary Hutzel, Mike Okuda, and executive producer Rick Berman. The original six-foot diameter model was built by Tony Meininger.
The model of Deep Space 9 (Lot #493) was sold at the 40 Years of Star Trek: The Collection auction on October 6, 2006 for US$132,000, including the buyer's premium (the winning bid was US$110,000).
The station was the very last model in the series to be replaced with an CGI model, which occurred in the very last pullback scene in "What You Leave Behind"; up until then, all footage shown of the station was of the physical studio model. The CG model was built at Station X Studios by Meni Tsirbas. David Stipes recalled, "Meni had created a Deep Space Nine station several years ago, and we talked at different times, but this was the chance to get involved. This was their one and only shot, but it's the final pay-off shot, and it's really beautiful. He's such a brilliant artist. It's all being done on LightWave, and it's great. The live action footage of Kira and Jake was "projected" by the LightWave software onto a polygon surface that was placed in the window of the CG DS9 station. We pull out of the DS9 window, until the station turns into a star. It's quite spectacular, because it's about 50 seconds long. That's the end of the show." (Cinefantastique, Vol.32, No.4/5, page 91)
The Star Trek: Deep Space Nine Technical Manual asserts that Deep Space 9 was equipped with Type-IX, -X, and -XI phasers. The Type-XIs were said to have been installed into retractable platforms stowed in the habitat ring. They make their first appearance in "The Way of the Warrior". The job of designing this new weaponry fell to the recently hired illustrator John Eaves. Herman Zimmerman gave Eaves detailed schematics of the station, and told him to find surface points where there were no moving parts, windows or existing weaponry, and to design never-before-seen, but plausible, phaser arrays and torpedo launchers to be positioned in such places.
Designing the station (interior)
As Herman Zimmerman explains, "Having determined what the outside of the station was going to look like, then we had an enormous job making the interior sets to match what the exterior looked like, so that believably, we were inside this alien, bizarre, highly technical and not necessarily understood by our Starfleet personnel, space station." (Deep Space Nine: A Bold Beginning, DS9 Season 1 DVD special features).
Zimmerman designed a list of ground rules about the look of the interiors: Cardassians like geometric symmetry, they prefer circles to squares or ovals, they like things in groups of three, and they favor dark colors (especially khakis and dark green).
In the novel The Battle of Betazed, there was a Terok Nor type station called Sentok Nor that was built in orbit of the planet Betazed following its occupation by Dominion forces in 2374, during the Dominion War. Sentok Nor served primarily as a maintenance facility and a Jem'Hadar hatchery, and as the Dominion's strategic command post for the sector. In addition, Sentok Nor was also the base of operations for Dr. Crell Moset's experimental efforts to give Betazoid telepathic skills to the Jem'Hadar. Sentok Nor was destroyed in 2375 by a Starfleet team that included Chief O'Brien, Lieutenant Commander Geordi La Forge, and Commander William T. Riker.
In the novella "The Slow Knife" from the anthology book Seven Deadly Sins, there was a Terok Nor type station called Tantok Nor that was was located on the outer edge of the Kelrabi system near Kelrabi IX in the Dorvan sector of the Alpha Quadrant. In the year 2362, Jagul Hanno led a fleet to Tantok Nor in order to counteract believed threats from the Federation along the border. During this time, the station was under the command of Gul Relaw, who took over command of Hanno's fleet after Hanno was recalled to Cardassia following the Setlik III massacre.