Slipspace guidance beacon
From Halopedia, the Halo wiki
Slipspace guidance beacons are Slipstream Space navigational aid devices used by the UNSC. Dropped into Slipspace by another vessel such as a prowler, they are intended to assist other vessels in performing short in-system jumps with more accuracy than otherwise possible, something that can be of considerable advantage in a space engagement. Even with the use of guidance beacons however, human Slipspace technology is not perfect, especially when the jump is performed near a significant gravity well. This was demonstrated during the Battle of Psi Serpentis in 2543, when a part of Battle Group India re-appeared from an in-system jump scattered from the main group despite guidance beacons planted by the prowler UNSC Wink of an Eye.[1]
