Salius VI

Multiple realities
(covers information from several alternate timelines)

Salius VI was the inhabited sixth planet in its star system. It was the site of a Federation penal colony in the 23rd century.

In an alternate timeline where Captain Christopher Pike avoided the accident that exposed him to delta radiation, Lieutenant Commander Una Chin-Riley was arrested for violating the Federation's prohibition on genetic engineering in 2259 and sent to Salius VI. She was still incarcerated there as of 2266. (SNW: "A Quality of Mercy")