Every day of the year tens of thousands of promising telepaths are brought before the Golden Throne to be bonded to the God-Emperor. This soul-bonding is the culmination of a long journey that started with their arrest and interment aboard a Black Ship, followed by an agonizing trip to Terra, then testing, training and indoctrination conducted by the Adeptus Astra Telepathica. Despite the seemingly vast number of graduate there are never enough astropaths - their duties are many (the Imperium is utterly dependent on their service) and their careers often short (astrotelepathy is a taxing trade).

The soul-bonding gives the telepaths the ability to send and receive data across vast distances - even across lightyears of empty space. It also hardens them to the horrors of the warp and makes them very resistant to possession. There is a price for such power; most astropaths are permanently blinded or otherwise crippled.

USE

Astropaths can send and receive data. They are in effect living psychic telecommunication devices. Techniques vary a bit, but all astropaths can read a text, convert it to astrotelepathic signals and then transmit. Another astrotelepath within range can receive and reverse the process, producing an identical text (barring any errors or disturbances in the transmission). Skilled astropaths can transmit more complex data; picts, audio, holograms, even sensory and emotional data. Most data is encrypted in some fashion.

RELAYS

Astropaths can’t send data clear across the galaxy. Instead they work through relays. Each Imperial world constantly scans for incoming signals, check for destination in the message header, and if necessary they pass on the message. This way a signal can leapfrog across the Imperium (duplication of messages is common, but that’s a strength and not a liability). Priority signals will be bumped to the top of the queue and/or passed on to high-grade transmitters.

CHOIRS

Astropaths either work alone or they pool their resources. Such groups are called Choirs. All major Imperial worlds will have one, but fringe systems might not.

GRADING

Astropaths come in four grades. Grading is most important when it comes to transmission - weaker astropaths can receive nearly as well their stronger comrades.

Grade 1: These rare individuals can send across vast interstellar distances on their own - across whole sectors, if not longer. If joined by a strong Choir their range is, if not unlimited, then nearly so (across as Segmentum).  They are reserved for use by the highest echelons of the Adeptus Terra.

Grade 2: The 'common' sort of interstellar transmitter. Can reach nearby systems, or further if joined by a Choir. Few commercial astropaths are of this grade (those few who are were originally typically graded as 3, but have since risen in skill and power).

Grade 3: The most common type of astropaths. Can receive well enough, but transmission range is limited to sub-stellar. Can be used in Choirs to boost signal strength, but they add but a little each. Most find use aboard Navy vessels in intra-fleet communications or take up commercial work if the Adepta have no need for their services.

Grade 4: These are they failed astropaths. They either have trouble transmitting, receiving or both. Some are strong, but cannot control the direction of their signal. Others are too weak to be useful. Yet others fail to grasp Imperial communication protocols and are forced to rely on symbolic or emotional communication. Few such astropaths are found in Imperial service – most must fend for themselves.

COMMERCIAL ASTROPATHS

The Adeptus Terra releases a percentage of astropaths for commercial use, conscious that the commercial sector, Imperial Governors and other factions have need of their services. Many, but not all, are weaker or otherwise second-rate (lack of control, lack of moral purity, etc.) astropaths. Some are released for reasons of corruption within the Adeptus Astra Telepathica. There is also said to be a certain trade in ‘non-sanctioned’ astropaths, whatever that is.