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"There isn't enough life on this ice cube to fill a space cruiser. Sensors are placed, I'm going back."
Han Solo to Luke Skywalker on Hoth[1]
A Rebel places a sensor beacon on .

A Rebel places a sensor beacon on Hoth.

Sensor beacons were security scanners and alarm systems that were typically deployed around large tracts of land, such as agricultural facilities, moisture farms, parks, bases and large wilderness areas. When properly placed and calibrated, a network of sensor beacons provided complete electronic surveillance of an area. The information gathered by the beacons was fed to a command station or central location which could then trigger an alert to any intrusions on the land.[2]

The Alliance to Restore the Republic used sensor beacons to guard their remote bases. The Alliance deployed Fabritech SE-Vigilant automated sensor beacons around Echo Base on the planet Hoth.[2]

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