Dark matter

"Exposing dark matter to normal matter would be cataclysmic. It would create a black hole, swallowing Tython in a heartbeat. The rest of the system too."

―Dam-Powl^[1]

Dark matter was an undetermined type of matter hypothesized to account for a large part of the mass of the universe.

History

"Dark matter interacts only gravitationally with the rest of the universe. It pools into clumps like ordinary matter, forming clusters and galaxies similar to the one we inhabit. Some scientists believe our galaxy to be surrounded by a halo of such galaxies—completely invisible to the eye, but there nonetheless. Danni and I were talking about this just yesterday. She wonders if such an invisible clump might explain the hyperspace disturbance in the Unknown Regions. A dark matter cluster could be in the process of colliding with our galaxy right now, passing invisibly through it, detectable only by its gravity. Clusters aren't uniform in density: they have dust lanes and empty bubbles—and stars, of course. The uneven distribution of dark matter might account for the difficulty we've had charting this region from the 'real' universe. It all comes down to a collision with another galaxy we can't even see—a collision taking place over billions and billions of years."

―Soron Hegerty, on the western barrier^[2]

Dark matter was present in the Deep Core, and was responsible for twisting the hyperlanes that made travel in the region so difficult.

In 25,793 BBY, Dalien Brock attempted to use a Gree device, powered by dark matter, as a means to leave the Tython system. If any of the dark matter used in the device were to have come in contact with normal matter then a black hole would have been formed, thus destroying the Tython system.^[1]

Darth Plagueis told his apprentice that due to problems in the Senate, the light was beginning to wane, pushed into retreat by dark matter.