Warp Drive
In Star Trek, Warp Drive is what happens when the captain says "Engage", "Make it so", or something else to similar effect. The stars form streaks of light around your ship, and off you go to explore strange new worlds...
Background
Warp Drive is the primary means Starfleet uses for faster than light travel. It was developed by Zefram Cochrane in 2061, with a first functional prototype operating at Warp 1 in 5. July, 2063. This historical event was responsible for mankind's first contact with extra-terrestial lifeforms, as a Vulcan science ship passing through the Solar System detected the Warp signature of the Phoenix, and decided that Humans were ready to be contacted.
Theory
- The Warp Core uses a controlled matter/antimatter reaction to create plasma (see Warp Core for details), which is then used to power various ship systems, and most notably, the Warp Drive. The plasma is led to the Warp Nacelles via plasma conduits. Once there, it is directed through the Warp Coils (there are 18 of these coils in a Galaxy-class ship), and each of these coils is sprayed with the plasma. The coils contain matter known as verterium cortenide, which transforms the energy contained in the plasma into a subspace field.
Each time a Warp Coil is sprayed with the plasma, a new field is formed. These fields then radiate outwards from the nacelles, and through interaction with each other, produce the warp field which propels the ship forward.
Subspace field stress is measured in Cochranes. Here is a table of Warp velocities and the amount of field stress they produce.
Warp 1 = 1 Cochrane
Warp 2 = 10 Cochranes
Warp 3 = 39 Cochranes
Warp 4 = 102 Cochranes
Warp 5 = 214 Cochranes
Warp 6 = 392 Cochranes
Warp 7 = 656 Cochranes
Warp 8 = 1024 Cochranes
Warp 9 = 1516 Cochranes
Note that the value of field stress in Cochranes corresponds to how many times the speed of light a ship is travelling. For example, a ship travelling at Warp 6 is travelling 392 times the speed of light.
Also note that the scale isn't linear, logarithmic nor exponential. Furthermore, once Warp 9 has been reached, a new a scale is required to account for the increased energy consumption due to the fact that subspace begins to cause severe drag at these speeds. This new scale is exponential, and has sometimes been called "Transwarp".
Miscellaneous Facts
A phenomenon called "Warp Threshold" states that it takes more energy to achieve a given warp factor than to maintain an already established field. This leads to situations where a ship travelling at Warp 4,8 takes more energy than a ship travelling at Warp 5. If they were to use a bit more energy to cross the threshold, the energy expenditure would decrease significantly.
Certain devices, like photon torpedoes and probes are fitted with a Warp Sustainer Engine, which allows them to maintain a Warp field if they were launched within one. Therefore torpedoes may be used in ship-to-ship combat while in Warp. Similarly, a saucer section seperated from the stardrive section may sustain a Warp field for a certain amount of time.
Source: Star Trek: The Next Generation Technical Manual