Devolin

The Devolin system was a trinary star system in the Alpha Quadrant. Circa 500,000 BCE, the third star of the system collapsed into a class-four black hole, creating a significant degree of ionizing radiation throughout the system. (ENT novel: Age of the Empress)

In 2358, the USS Pegasus, crippled by an explosion and shifting molecular phase, drifted into the Devolin system, where it shifted into normal space within a large asteroid. The USS Enterprise-D and the IRW Terix both searched the Devolin system in 2370 for the wreckage of the Pegasus. (TNG episode: "The Pegasus")

In the Mirror Universe, the Devolin system was the suspected location of a rebel fleet planning an attack against the Terran Empire. However, when a fleet led by the USS Defiant arrived to attack the rebels, they found no other ships. (ENT novel: Age of the Empress)