Crystal gravfield trap

A crystal gravfield trap (CGT) was an expensive type of sensor that used a synthetic crystal grid to detect and identify fluctuations in the local gravity field. High quality crystal gravfield traps could detect and identify fluctuations for hundreds of thousands of kilometers around the device. They could be blocked by the presence of mass, not being able to detect a ship on the far side of a planet due to its mass.

CGTs were the only sensor that could reliably detect a ship with an active cloaking device. Bartokk assassins hired by Groodo the Hutt had access to a CGT sensor and thus were able to detect the cloaked Sith Infiltrator of Darth Maul.

When Grand Admiral Thrawn blockaded Coruscant with a number of cloaked asteroids, locating them became a top priority. The New Republic did not possess any CGTs, and so was required to attempt to steal one from the Imperial base at Bilbringi. New Republic General Garm Bel Iblis had one before the Siege of Svivren, but it became lost.

The LightStealth-18 Reconnaissance Ship, used by the New Republic during the Yuuzhan Vong War, was equipped with such devices as part of its sensor array.

The Imperial Remnant had Imperial Patrol Frigates equipped with crystal gravfield traps and used as deep-space probe ships.

Text and facts from the “Crystal gravfield trap” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.