The magnetometric guided charge is a starship-mounted weapon used by the Borg, capable of auto-acquiring a metallic target under conditions in which sensors are ineffective. In 2366, a Borg cube forced the USS Enterprise-D from its hiding place inside the Paulson Nebula by firing magnetometric guided charges into the cloud. After a few charges exploded nearby, Enterprise sustained a direct hit on deck nine, prompting Picard to take the ship out of the nebula. (TNG: "The Best of Both Worlds" )