An Auspex, also called a Surveyor, a Multi-scanner, or simply a Scanner, is a short-ranged Imperial sensor device used to detect motion, invisible gases and energy emissions across a wide band of the electromagnetic spectrum. This includes such emissions as heat, radiation and most forms of energy given off by vehicles and living troops. Their main tactical use is for triangulating the location of otherwise hidden enemy forces so that they can be fired upon by Imperial troops. The standard range of an Auspex is fifty metres, although walls more than fifty centimetres thick as well as certain types of building materials are able to block their active and passive sensor modes. An Auspex can take the form of a separate hand-held device, or its mechanism may be built into a helmet such as in the case of Adeptus Astartes Power Armour and Terminator Armour. The Imperial Guard uses hand-held scanners known as Surveyors, though the technology is essentially identical. The Space Marines and other Imperial forces like the Orders Militant of the Adepta Sororitas, the forces of the Inquisition, the Adeptus Arbites and the Imperial Navy use the Auspex. Similar technology is used by the Chaos Space Marines and the other Forces of Chaos like regiments of Traitor Imperial Guard who make use of former Imperial technologies.
Long-ranged sensors like those used on Imperial voidships are often referred to as Augurs, though they make use of the same technology as the Auspex, save with far greater range and power when in active scanning mode.
- Codex: Space Marines (6th Edition) (Digital Edition), pg. 414
- Warhammer 40,000: Rogue Trader Rulebook (1st Edition), pg. 143