System Survey
In order to maintain up-to-date information on the Imperium and the regions surrounding it, The Imperial Interstellar Scout Service conducts survey on an ongoing basis. Although all systems are surveyed, not every system is surveyed to the same degree of detail. The Scouts divide their system surveys into five classes:
Class I
These surveys are the most brief, usually taking four to eight hours to complete. Probles and landing parties are almost never deployed. The Scouts reserve Class I surveys primarlly for the survey of a new system.
Whenever an unsurveyed system is first encountered, the Scouts have a standing order: Performa a Class I survey from interstellar range on the new system as soon as possible. A Class I survey may be conducted from as far away as one to two parsecs—close enought to allow the determination of basic stellar data and the possible presence of gas giants. The key goals are: chart the precise location of the new system, determine the system ecliptic, note stellar data, and estabisht the presence of large gas giants, if any.
Class II
This kind of survey takes an average of four to eight days, and may use probes at the commander's initiative. Landing parties are rare. Class II surveys are usually used as the first insystem survey of a new system or as a special survey to determine only a limited amount of information. The survey ship is sent into the system for a specific purpose, and leaves as soon as the question has been answered.
In a Class II initial system survey, all planetery bodies over 800km in diameter are noted, as well as any planetary satellites over 200km in diameter and the densitity of asteroid belts and rings are measured.
Class III
These surveys, which are the most common, take four to eight weeks, including the deployment of probes into the habitable zone. Landing parties may be used at the commder's initiative.
The scouts perform physical profiles of all significant bodies, and do an ephemeris of the bodies' orbial motions. An orbital map of the main world is made. Using orbital examination, the Scouts determine a preliminary UWP. As the commander's discretion, the WUP may be augmented by some on-planet observation and exploration.
Class IV
A class IV survey takes up to a year. Probed are sent into the system's habitable zones, and landing parties visit the habitable zone's worlds.
The most common Class IV survey undertaken by the Scouts is the intesive study of the main world. The world's surface is accurately mapped. Explorers examine the basic geology of the world and collect organizms so as to type the indigenous biology. Native sophonts are studied, but not usually contacted.
Class V
These surveys take five to 10 years. Probes and landing parties are sent to all surveyed bodies. In most cases, an extensive Class V survey is performed only when requested by the surveyed system's government or by the Imperial military.
A common reason for a Class V survey of a system is as a precursor to colonization. The Scounts undertake many detailed and time-consuming studies; they model planetary dynamics (including atmosphere, oceans, solar, vulcanism, and major migratory patterns), and the measure the stability of the climate. Basic resources necessary to sustain a colony are identified. A superficial examination of resources useful in economic exploitation is made, and native sophonts, if any, are contacted.