Clairvoyance

All physical matter is connected, both through space - particle-to-particle - and through time - cause-to-effect. Clairvoyance is all about reading these material connections. Using it, Travellers can spy on a remote location without actually being there, explore an area without even moving, or touch an object to interpret its physical past - such as examining a hole in the wall to find out what made it.
Such insight, whilst an astounding natural ability, is often muddy and the clarity received depends on the Effect of the Clairvoyance check. Even budding clairvoyants can expect to receive overall impressions and key concepts from their readings, but only the most-experienced can reliably achieve the Exceptional Successes (6+) required for "perfect" levels of clarity - i.e. interpreting the reading as though they were really there with almost no time lag.
Travellers do not need to have personally visited a location to target it with clairvoyance, but they must at least know where to aim. Unlike precognition though, Travellers can explore their visions freely once they begin, and can even extend a vision's duration with extra PSI points if necessary. Clairvoyance is strictly concerned with physical phenomena, and cannot be used to sense thoughts, feelings or abstract facts. Living creatures, despite being physical entities, cannot be directly targeted with clairvoyance for similar reasons - but items on their person can at a DM-2. For any abilities which require physical contact, touch must be made with bare skin or through thin clothing.

Sense

The basic power to sense things about a location or object, making the Traveller aware of its most rudimentary characteristics or context. For example, the Referee could give a basic description of a distant location: 'a room, containing four dogs' or 'an open plain with a tree and no animals or people present'. Or they could give an impression of a location or object's recent past: 'this gun was recently fired' or 'this area was recently underwater'.
This power will generally focus on the most interesting or important feature within the target range, but only basic answers can be interpreted by this power regardless of Effect. If trying to determine an object's past, direct physical contact is required.
Check: Routine (6+) Clairvoyance check (1D rounds, PSI)
Reach: Very Distant
PSI Cost: 1

Footprint on the Sand

Technically, what a psychic senses through clairvoyance is not what actually happened, it is the causal interpretation of an event's impact on physical matter - the molecular "footprint" that a situation leaves on its environment.
Such footprints can be somewhat spoiled by the impact of other past-present events (by other footprints, if you like), which is why most clairvoyant visions appear less-than-realistic. Fortunately, clairvoyants are naturally drawn to the details that most concern them, so whilst a reading may be brief, inexplicable, or untimely; accurately-aimed clairvoyances should never be completely useless.

Spatial Perception

By making direct physical contact, the Traveller gains a greater sense of their surrounding environment. This grants them awareness of its primary terrain, features and obstacles, and allows them to ignore the effects of darkness, smoke, fog or other environmental effects that impede mundane vision. They may also detect hidden creatures or physical dangers within range. The Effect of the check determines the number of rounds this power lasts once contact is broken.
Check: Average (8+) Clairvoyance check (1D rounds, PSI)
Reach: Medium
PSI Cost: 2

Set Echo

The psychic imprints an echo of themselves onto a solid object, allowing them to target that entity with their clairvoyant powers even if they don't know its location. Additionally, imprinted items can always be targeted with Sense even if beyond the power's usual range.
Imprinting lasts for a number of years equal to the Effect of the check. This ability costs no PSI points to activate, but clairvoyants can only be imprinted onto a number of objects at once equal to their Clairvoyance skill level. Both imprinting and removing an echo requires direct physical contact with the target object. The echo is also lost if the target object is destroyed.
Check: Difficult (10+) Clairvoyance check (1D x 10 seconds, PSI)
Reach: Personal
PSI Cost: 0

Clairvoyance

This specific power allows a vision of some displaced point. The Effect of the check determines the level of detail perceived. A simple success may only show a location's shadows, with perhaps a single key item or person shown as clearer than the rest. An exceptional success allows one to see and explore a location with perfect clarity.
Check: Average (8+) Clairvoyance check (1D rounds, PSI)
Reach: Very Distant
PSI Cost: 1 per 1D minutes

Clairaudience

This power is identical to clairvoyance, with the exception that it allows hearing instead of seeing. Marginal successes may only indicate the general sounds of a room: two people talking, two people arguing, silence, machinery working, a dog barking, etc. Average or Exceptional successes allow more detailed listening, or a focus on specific sounds.
Check: Average (8+) Clairvoyance check (1D rounds, PSI)
Reach: Very Distant
PSI Cost: 1 per 1D minutes

Clairtangency

By physically touching an object or location, the psychic senses an important physical fact regarding the target's past. Depending on the Traveller's priorities, this power could impart knowledge of an object's owner, or of how the item was generally used, or of a situation in which the object was directly involved.
The past is hard to read, and so Effect is halved to determine the clarity of the information received and how far into the past the psychic can reach. To assist with this, Travellers may spend extra PSI points to increase the Effect after its halving. Basic successes may only give a general idea of what recently happened to an object, whilst Exceptional Successes may grant the Traveller a clear view of that object's creation - even if it occurred centuries ago.
Check: Difficult (10+) Clairvoyance check (1D rounds, PSI)
Reach: Personal
PSI Cost: 2+

Claircognizance

The clairvoyant scans the area around them for a specific object that they have had significant physical contact with, either from handling it regularly, from imprinting onto it using Set Echo, or from recently having spent a few focused minutes holding it. If successful, the psychic learns that item's exact location. Clairvoyants are famous for never losing their keys.
Check: Easy (4+) Clairvoyance check (1D seconds, PSI)
Reach: Medium
PSI Cost: 1

Clairsentience

This powerful technique is very difficult to achieve, but if successful a Traveller is able to both see and hear at a specific location with absolute clarity - as if undetectably present in the room themselves. Since clarity is always perfect, the Effect of this power instead increases the possible duration in timeframe levels (see p62 of the Core rules).
Check: Very Difficult (12+) Clairvoyance check (1D x 10 seconds, PSI)
Reach: Very Distant
PSI Cost: 2 per 1D x 10 seconds (timeframe may increase due to Effect)

Seeing "Everything"

Unsurprisingly, the ability to spy and eavesdrop with no chance of detection makes people very uncomfortable - especially to those unaware of a clairvoyant's limitations, who simply assume that they can always "see everything". They may not be quite as feared as telepaths, but they are a relatively-close second - and clairvoyants who wish not to be shunned usually hide their abilities.
Clairvoyants are of course in high demand in espionage, though even then they are suspect - many clairvoyant spies are kept far, far off-site for security reasons. There are advanced technologies that can scramble a clairvoyant's perceptions, and the presence of a single brainguard is more than enough to negate their usefulness, but both of these countermeasures are uncommon - so those interested in keeping their secrets tend to hide even the location of their most-private conversations.