Galaxy 517 is a stellar region within the galaxy's Alpha or Beta Quadrant.
History[]
Prior to 2266, this region was unexplored by the Federation.
In 2266, the starship USS Enterprise traveled just inside the edge of Galaxy 517 with orders to proceed with caution. James T. Kirk and Spock made first contact with the inhabitants of the planet Alpha 332 after Nyota Uhura unexpectedly picked up lifeform sounds near a volcano. (TOS comic: "The Gods Have Come!")