- "I believe [the Celestials] engineered the hyperspace barrier that surrounds our galaxy, either to protect themselves against invasion or to prevent the return of beings they had exiled from this galaxy. Perhaps both. And I believe they engineered the chain of hyperspace anomalies that have long frustrated exploration west of the Deep Core....the western barrier...once extended across the entire galaxy, dividing it in two, but is now decaying and gradually retreating toward the Core."
- ―Insmot Bowen to Bevel Lemelisk, Conan Antonio Motti, and Arhul Kurumenga, 1 BBY
It was originally thought that hyperspace travel outside the galaxy was impossible because of a hyperspace disturbance at the edge of the galaxy. The goal of the Outbound Flight Project was to use the combined abilities of six Jedi Masters and twelve Jedi Knights to penetrate the disturbance using the Force. The Yuuzhan Vong found that they were able to bypass it at an area they called Vector Prime. The Yuuzhan Vong also possibly entered the Crispin system, which was at the very edge of the galaxy at the outer border of Wild Space.
The midline of this field that surrounded the galaxy almost exactly corresponded to the portion of the Unknown Regions that bordered the "western" quarter of the galactic disc. This segment of the Unknown Regions was historically impenetrable to conventional hyperspace mapping attempts by the Old Republic.
Behind the scenes
- Star Wars: Knights of the Old Republic
- Outbound Flight (Mentioned only)
- The New Jedi Order: Vector Prime (First mentioned)
- The Essential Chronology
- The New Essential Chronology
- The Essential Atlas
- The Essential Guide to Warfare
- Star Wars: Edge of the Empire Core Rulebook
- Dangerous Covenants