Space

Space, also known as spacetime or more fully as the spacetime continuum, is the plane of existence home to the known universe.

When a starship reaches the speed of warp 10, it exists at every point on the spacetime continuum at once, e.g. in superposition.

The Krenim weapon ship used by Annorax worked by pushing the target outside the spacetime continuum, thus deleting it from history.

Disruption to the spacetime continuum can have serious repercussions. In 2368, for example, the USS Enterprise, NCC-1701-D--D unknowingly entered a rupture in the space-time continuum, which threw the ship and its crew into a temporal causality loop, experiencing the same time frame over and over.

Similar phenomena, such as spatial ruptures or subspace rifts, have been encountered by numerous starships throughout the galaxy.

The term deep space describes areas of space that are farther than one's own solar system. This term is used in Star Fleet nomenclature to describe the location of certain types of starbases, outposts and space stations. For example, Deep Space Station K-7 or Deep Space 9 are named based on their deep space locales.

According to records, the USS Farragut, 23rd century was the first deep space assignment of Lieutenant James Kirk.

In 2266, on the stand in a court martial proceeding, Dr. McCoy was cited on record as an expert in psychology, especially space psychology, which was defined as "patterns which develop in the close quarters of a ship during long voyages in deep space."

In 2268, Spock described the damage of space probes Nomad and Tan-Ru as occurring in deep space. Later, Captain Kirk ordered the errant amalgam of the two probes beamed to a set of coordinates that were specified as being in deep space.

Kirk also specified deep space as a target when Redjac, inhabiting the body of Hengist, was transported off the Enterprise.

When Lieutenant Mira Romaine came aboard USS Enterprise, NCC-1701 , Dr. McCoy and Montgomery Scott had a discussion about how their experience told them that someone's first trip into deep space can affect them.

The USS Voyager was the first Federation ship which tested a Class nine warp drive in deep space.

After the first contact with the Voyager in 2374, Star Fleet redirected two deep space vessels toward Voyager's position.

It is never mentioned what the exact definition of "deep space" is, but it is clear that some Federation ships are ordered to "deep space missions" or that some starbases are called "deep space stations". The insinuation, however, is that deep space refers to regions of space that are "far from home".