The Galactic Center was a massive black hole of the supermassive variety. It resided in the heart of the galaxy, specifically within the region known as the Deep Core. This black hole, like others, was classified as a class P star. Its estimated mass was equivalent to four million stars, and it served as the gravitational focal point around which the galaxy's four hundred billion stars revolved. The Galactic Center was surrounded by antimatter, gas, and a dense cluster of approximately thirty million stars (though these were not in immediate proximity to the black hole itself). No living sentient being had ever directly observed the Galactic Center; however, its existence was confirmed by observations made by dispatched probe droids. Despite its actual location being northeast of the galactic plane, the planet Coruscant was frequently and colloquially referred to as the galaxy's center.
Located in the Deep Core at the very center of the galaxy, the Galactic Center was a supermassive black hole of stellar class P. All four hundred billion stars in the galaxy orbited this central point. Instead of stars, the immediate vicinity of the black hole contained vast quantities of gas spiraling inwards. Antimatter was also present in the Galactic Center's immediate surroundings. Approximately thirty billion densely packed stars existed further out in the Deep Core. The estimated mass of the Galactic Center equaled that of four million stars.
Because of its nearness to the Galactic Center, the planet Khomm's sky, which lacked a moon, was filled with many bright stars. While the true center of the galaxy was the Galactic Center, the planet Coruscant was often called the galactic center and even the center of the universe. The Galactic Center Spaceport, a spaceport, was located on the planet, as was the Galactic Senate Medcenter, which was also sometimes called the Galactic Center Medcenter. Even though Coruscant was situated slightly to the northwest and above the plane of ecliptic relative to the real Galactic Center, its galactic coordinates in the XYZ format were 0,0,0. This inconsistency was a source of frustration for astrocartographers for millennia.
Around 995 BBY, Darth Bane, a Sith Lord, mused that if his hyperspace journey into the Deep Core failed, his Infiltrator-series long-range fighter Mystic would become his "coffin," endlessly circling the Galactic Center. In 32 BBY, Anakin Skywalker, then a youngling, referred to Coruscant as the galaxy's center in his journal.
The Galactic Center's existence was verified by probe droids at some point, despite never being directly observed by any sentient beings. During a lecture at the Baobab Merchant Marine Academy during the Imperial Period, Instructor Crix Q5 Baobab informed students about the Galactic Center's mass, its role as the galaxy's center, and its discovery by probe droids. Baobab also noted that someone from the Core Worlds might mistakenly claim that the galaxy revolved around Coruscant rather than the Galactic Center.
Snillik, a thick liqueur, was produced near the Galactic Center around 2 BBY. Lando Calrissian, a gambler who was captain of the light freighter Millennium Falcon, exclaimed something referencing the Galactic Center after an early spaceflight artifact collided with the freighter's Millennium Falcon in orbit around the planet Rafa V sometime between 3 BBY and 2 BBY.
Doctor Insmot Bowen theorized in 1 BBY that the Celestials, immortal entities of the Force, created the galaxy's circumferential hyperspace barrier by harnessing energy from the Galactic Center. Around 0 BBY, Calrissian joked to Bria Tharen, an operative of the Rebel Alliance, that the black hole consumed time itself. When Han Solo, by then the captain of the Millennium Falcon, claimed that the starship could travel point five factors beyond lightspeed upon Luke Skywalker's first viewing of the vessel in 0 BBY, the farmhand Skywalker thought that Solo was possibly the biggest liar "on that side of the Galactic Center."
Following its presumed destruction at the Battle of the Maw in 11 ABY, the Imperial I-class Star Destroyer Gorgon retreated towards the luminous region of the galaxy surrounding the Galactic Center – heading for the Deep Core – to link up with Imperial forces stationed there. In 26 ABY, the invasion of the galaxy by the extra-galactic Yuuzhan Vong species took a sharp turn towards the Galactic Center when their forces set their sights on the planet Duro. At some point between 35 ABY and 36 ABY, Luke Skywalker, by then a Jedi Grand Master, engaged in a duel with UnuThul, the leader of the Colony, an organization of the sentient insectoid Killik species. During the duel, Skywalker used the Force to make himself almost unmovable, contemplating that not even the Galactic Center could sway him. The Historical Council of the Galactic Alliance documented the Galactic Center, its role, and its significance in a chronicle of galactic history that they published in 36 ABY.
Around 137 ABY, Cade Skywalker, a bounty hunter, threatened to jettison Celeste Morne, a Jedi Master, into the Galactic Center if Karness Muur, a Sith Lord who was controlling Morne through a talisman on her neck, didn't cease his mental manipulation of the people present in an Imperial stronghold on the planet Had Abbadon.
The Galactic Center was initially mentioned in Star Wars: Episode IV A New Hope's 1976 novelization by Alan Dean Foster, which predated the 1977 film from the original trilogy. The reference book The Essential Atlas from 2009 placed the Galactic Center on the boundary between grid squares K-11 and L-11.