Memory Alpha

Memory Alpha is the planet where the largest Federation library is kept. (TOS episode: "The Lights of Zetar")

History
After an attack on it by beings from Zetar, the Symphony Alpha complex was also built on its surface, headed by Commissioner Mira Romaine. (game: Star Trek: Starfleet Academy - Strategic Command)

In 2374, Jadzia Dax consulted Memory Alpha for information on the Grigari. (DS9 game: The Fallen)

Chi Namthot of Memory Alpha had made extensive research notes on the Iconian Gateways prior to 2376. (DS9 Gateways novel: Demons of Air and Darkness)

After the death of Shinzon, researchers at Memory Alpha completed a study to determine what would have happened if the mad Praetor had not been stopped. The published preliminary analysis revealed that both the Alpha and Beta quadrants would have been consumed by total thalaron war which would have made a new dark age that would have consumed and devastated entire civilizations. The aftermath would have resulted in surviving powers being too weak to challenge the Borg Collective. (TOS novel: Captain's Blood)