Ananke Alpha is a maximum security, top secret Federation prison space station complex. The complex was located in an extremely remote star system with no planets.
History and specifications
It was constructed in the 2320s decade as a facility to hold extremely dangerous criminals and those who were difficult to detain. It was of a spherical design. (DS9 - Worlds of DS9 - Volume Three novella: The Dominion: Olympus Descending)
Following the Dominion War, the Female Changeling was imprisoned at Ananke Alpha. (DS9 - Worlds of DS9 - Volume Three novella: The Dominion: Olympus Descending, ST website: The Path to 2409)
Shortly after the end of the war, a small group of Cardassian commandos, part of the Rom Knights, broke in to the facility with the intent of assassinating the Female Changeling, but their mission was a failure. (ST - Alien Spotlight comic: "Cardassians")
First Splinter timeline
In the year 2376 in the First Splinter timeline, Captain Kira Nerys took Taran'atar to Ananke Alpha aboard the runabout Rio Grande to meet the Female Changeling. (DS9 - Worlds of DS9 - Volume Three novella: The Dominion: Olympus Descending)