Quadrant

A map of the Milky Way's four primary quadrants

In stellar cartography a quadrant is a large region of space encompassing a portion of a galaxy. In general, the galaxy is divided into four equally sized, cubic quadrants, defined by one meridian passing through the galactic core and a second one perpendicular to the first, that also passes through the galactic core. In the case of the Milky Way Galaxy these four quadrants are referred to as the Alpha Quadrant, Beta Quadrant, Gamma Quadrant and Delta Quadrant.

The four main quadrants

The United Federation of Planets and its neighboring powers, including the Klingon and Romulan Empires were located in the Alpha and Beta Quadrants, whereas the Borg Collective was located in the Delta Quadrant, and the Dominion in the Gamma Quadrant. (Star Trek VI: The Undiscovered Country; ENT: "Regeneration"; DS9: "Rules of Acquisition")

During the early exploits of Earth Starfleet's Enterprise NX-01, under Captain Jonathan Archer, it was remarked by Vulcan Ambassador Soval that "in less than a single Earth year you've engaged in armed conflicts with over a dozen species. You've escalated the conflict between my people and the Andorians which included the destruction of one of our most sacred monasteries. You helped eighty-nine Suliban escape from detention. You may claim to be on a mission of exploration. I, however, consider you reckless and irresponsible. A danger to the quadrant." (ENT: "Shockwave, Part II")

On stardate 3087.6, the USS Enterprise encountered violent, unexplained stress and force while investigating an uncharted planet. According to Captain Kirk, the effects were felt for at least this entire quadrant of space. His suspicions were confirmed by Commodore Barstow, who explained the scope of the effects, which he described as having occurred in every quadrant of the galaxy and far beyond. (TOS: "The Alternative Factor")

Sectional quadrants

Some smaller sections of the galaxy were historically referred to as a quadrant as well, including Quadrant 448, Quadrant 904, Morgana Quadrant, and the Drema Quadrant. (TOS: "The Squire of Gothos", "The Deadly Years"; TNG: "The Child", "Where Silence Has Lease", "Pen Pals")

These references were comparable in reference to a sector. (TOS: "Charlie X", "Errand of Mercy", "The Trouble with Tribbles"; TAS: "More Tribbles, More Troubles", "The Pirates of Orion"; DS9: "Trials and Tribble-ations") In one instance, the USS Enterprise-D picked up an unusual disturbance "in a nearby quadrant," which was confirmed as being Sector 63. (TNG: "Conspiracy")

During the 2260s, the planet Argelius was of strategic importance as a space port to the Federation. At the time, it was the only port in that quadrant. (TOS: "Wolf in the Fold")

Also during this time, the quadrant of space that included such notables as Deep Space Station K-7, Donatu V and Sherman's Planet, had been under dispute between the Federation and Klingon Empire since initial contact. In 2268, Nilz Baris served as the Federation Undersecretary in charge of Agricultural Affairs in said quadrant. (TOS: "The Trouble with Tribbles")

Following the loss of the shuttlecraft Galileo in the Murasaki Effect in 2267, the Enterprise shuttlecraft Columbus conducted a search of Quadrant 779X by 534M. After reporting negative results, the shuttle was ordered by Captain Kirk to proceed to the next quadrant. (TOS: "The Galileo Seven")

On stardate 5710.5, the Enterprise was exploring an outer quadrant of the galaxy when it received a distress call from the planet Scalos. (TOS: "Wink of an Eye")

While under the command of Captain Kirk, the Enterprise was on several occasions the only authorized or available ship in the quadrant in times of crisis.

During the transport mission to Babel, the Enterprise encountered an unidentified vessel that was shadowing their route. Following contact with Starfleet, the Enterprise received acknowledgment which confirmed that there was "no authorized Federation vessel in this quadrant." (TOS: "Journey to Babel")

On stardate 5818.4, the Enterprise was ordered to respond to a botanical plague that was devastating a planet in the quadrant of the galaxy where the Enterprise was at the time operating. (TOS: "The Cloud Minders")

When the Enterprise encountered Kukulkan's starship, it was noted that Starfleet listed no other authorized vessels in that particular quadrant. (TAS: "How Sharper Than a Serpent's Tooth")

When the Enterprise was ordered to Regula I by Starfleet Command in 2284, Admiral Kirk informed them that "all we had was a boatload of children," but they were nevertheless diverted because they were, according to Starfleet, "the only ship in the quadrant." While en route to Regula, the Enterprise encountered the USS Reliant, under the command of Khan Noonien Singh. Once the two ships were in visual range of each other, it was noted that the "Reliant in our section. This quadrant, sir, and slowing." (Star Trek II: The Wrath of Khan)

This reference seems to indicate that a "quadrant" refers to a portion of a "section," the smallest portion of space associated with the term.

The planet Aldea was located in "Quadrant 1, mark 9-0" by the USS Enterprise-D in 2364. (TNG: "When The Bough Breaks")

Later that year, the Enterprise-D received a communique from Starfleet reporting a battle in "Quadrant 9, coordinates 070, mark 3" in the Klingon Neutral Zone. (TNG: "Heart of Glory")

Background

According to the Star Trek Encyclopedia, "quadrants and sectors have been used inconsistently in various Star Trek episodes and films. During the original series, the term quadrant was used rather freely, as was the term sector. At times, quadrant seems to refer to a fourth of the entire galaxy, while at others it seems to be a portion of a smaller region. It was not until "The Price" (TNG) that the current system of Alpha, Beta, Delta, and Gamma quadrants was firmly established. Star Trek VI: The Undiscovered Country adhered to this system, as well."

Additionally, Bjo Trimble explained in the Star Trek Concordance that a quadrant is "an area of space (a misnomer, as it should be called an octant)."