A FTL detection system using the properties of Subspace to detect vessels either in FTL flight or sub-light flight. Used for both early warning and navigation, the Abwehrans also use it for long-range, real-time targeting. Though, while it is a Faster Than Light, powerful detection system, it doesn't give an operator much detail. Not only does it only detect the mass of an object, but it can only detect objects above 60,000 kilograms (60 metric tons). While this isn't much of a problem for space craft, the Powered Armor of Yamatai are literally invisible to this detection.

With the ability to have detection ranges reaching out of solar systems, Station-based subspace mass sensors are the most powerful detection systems in the Abwehran arsenal. With a maximum passive range of 100 Light Days (17,314 AU) and a active range of a full Light Year, Station Subspace Sensors make stations key components of system-wide defenses.