From publisher blurb:
Hyperspace allows for speedy travel across the gulf of stars. Without it, a space voyage across any substantial distance would require centuries, rather than hours or days, to complete. Not surprisingly, the laws of physics operate differently compared to normal space, and as a result starship captains and their crews must contend with all manner of strange anomalies, unexplained stellar singularities, and unpredictable hazards as the traverse hyperspace. A number of these have become legendary among spacefarers, forming the basis for tall tales and ghost stories. Here are nine anomalies that exist within hyperspace. Some of these rare phenomena pose navigation hazards, while others produce weird, even magical, effects. The GM can use these anomalies to challenge adventurers, to serve as unusual adventure locales, or to provide story hooks for future adventures.
This sourcebook contains the following: Fluidic Space, Haunted Space, Phantom Field, Oppositional Anomaly, Sargasso, Sunken City, Time Dilation Anomaly, Translocational Field and Unreal Space.