Terrain-following sensor

A Terrain-following sensor (TFS) was a type of sensor which used optical, sonic and radiation sensors to cut through obstructions such as dense cloud cover and forest canopies to map out topographical details in near-instantaneous time. When used in conjunction with a navigation computer, a TFS could help plot a course through dense unmapped areas, identifying potential hazards and landing zones.

Han Solo utilized the Millennium Falcon's TFS in order to evade Imperial TIE Fighters during their pursuit through the Hoth asteroid belt. Unfortunately, it also misidentified an Exogorth as part of a deep cavern in which the vessel could hide in, a mistake which nearly proved deadly.

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