The central secret of interstellar travel is jumpspace. Without jump,
interstellar travel would be restricted to the universal speed limit of light
speed, and intelligent species would never travel to the stars. Jump
allows travel at speeds of up to six parsecs per week.
The basic concept of interstellar travel is that of an alternate space. Theoretically,
jumpspaces are alternate spaces, each only dimly understood from the standpoint
of our own universe. Jump is defined as the movement of matter from one point
in space (called normal space) to another point in normal space by
travelling through an alternate space (called jumpspace). The benefit
of jump is that the time required is relatively invariant - about one week.
If the distance travelled is greater than can be covered in one week in normal
space, then a gain has been made. Jumpspace makes possible enormous gains.
Entering jump is possible anywhere, but perturbations due to gravity make
it safest to begin a jump at least 100 diameters out from a large massive
body such as a world or star. Ships are naturally precipitated out of jumpspace
before they get too deep into a gravity field.
Normal jumps take 168 hours (plus or minus 10 percent) to complete, regardless
of the distance travelled.
Sometimes a jump goes wrong. Catastrophic failures (called misjumps)
can destroy the ship and its crew. Other failures can destroy a drive or
send a ship in the wrong direction. Some misjumps reduce a jump-6 to a mere
jump-1, or convert a jump-1 into jump-10, 20, or higher.