smart weapon, missile or steerable bomb equipped with a laser, television, or satellite guidance system. Smart weapons, which use guidance systems that rely on external assistance, are distinguished from brilliant weapons, which are totally self-guided. In the case of a smart bomb with a laser guidance system, an aircraft pilot aims a laser beam at the target, a computer keeps the beam locked on the target, and the bomb has a sensor programmed to find the reflection of the laser's light. A guidance computer adjusts the path of the bomb after it is released, using movable fins to steer. A television guidance system uses a television camera in the nose of the weapon to lock onto the image of the target identified by the pilot. Satellite-guided bombs have guidance computers that use signals from navigation satellites to confirm that they are on target; the tail fins are adjusted to control the bomb's course as it falls. Cruise missiles also utilize information from navigation satellites to maintain a proper course during flight. Extensions of smart-weapon technology are off-road mines that can "listen" for moving vehicles and attack them, "thinking" antipersonnel mines that are activated or deactivated automatically after a set period of time, and missile and artillery fire targeted by space-based intelligence-gathering satellites.