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DRADIS can be used in stationary configurations as well on ships. A group of Cylon Centurions are able to jury-rig a DRADIS assembly from their Heavy Raider into a stationary tracking array in an attempt to eliminate any SAR missions from Galactica (TRS: "Fragged").
A "DRADIS contact" is an object or objects detected by DRADIS. Contacts are typically identified by cross-referencing with an IFF system (in the case of ships) or an astronomical database (in the instance of planets or other celestial bodies).radiological alarms.
DRADIS is likely a central component of the navigation computer on Colonial ships such as battlestars, as they do not navigate in sublight mode by visual means. Galactica's tactical and navigation data is displayed on a series of screens that form the DRADIS console, suspended above the CIC's Command and Control console.
The DRADIS can be blinded by external sources of electromagnetic radiation such as artificial radiation by EMP generators (TRS: Miniseries), nuclear detonations (TRS: "Pegasus", "Razor"), pulsars (TRS: "Sacrifice"), star clusters and binary stars (TRS: "The Passage", "The Captain's Hand"), or other phenomenona such as the nebula around New Caprica (TRS: "Lay Down Your Burdens, Part I").
Carbon composites absorb and diffuse DRADIS scans, rending any vehicle comprised of such material largely invisible (Flight of the Phoenix). Conversely, false positive contacts can be induced through electronic interference or malfunction, producing contacts that either misrepresent their actual configuration or do not actually exist. In the case of the latter, such false positives are referred to as "ghosts" (TRS: "Exodus, Part II", "The Oath").
Sourcing of the term
The "Direction, RAnge, and DIStance" breakdown of the acronym "DRADIS" was listed in an early manuscript of the first half of the Miniseries. Since some major elements of this script were changed (such as Kobol being the sole home of the Colonies, and not separate worlds) in comparison to the completed teleplay, canonical use of this breakdown should be taken with some skepticism.
There is some evidence to suggest that the original breakdown is the canonical version. In "Kobol's Last Gleaming, Part I", Crashdown performs a DRADIS sweep of Kobol. The aerial survey is later presented to the President. For a brief moment, as Roslin takes the survey image out of Billy Keikeya's hand, the DRADIS information printed on the image is visible. The letters on the image are clear and are as follows:
The letters represent numerical values. While this is not conclusive evidence, it is consistent with the original manuscript definition.