Kendalaran Hyperspace has been described as a semi-stable hyperspace anomaly which can exist only inside the Rhid-Kendalaran Nebula. It seems to act like a system of wormholes, allowing faster-than-light travel between certain set points within the nebula even without the guidance of the Force. However, there is no telling how long it will take for a ship to travel between those points: one week it may take only 12 hours; the next week, it may take the same starship four days to make exactly the same trip. It has also been known (very rarely) to take negative amounts of time, resulting in a starship appearing at the other end as much as a full day before it actually entered Kendalaran Hyperspace. The psychological effects on the crew of such a starship can easily include varying levels of temporary or permanent insanity both before and after the jump. The Pirates of the Rhid-Kendalaran Nebula have learned to program their nav-computers not to enter Kendalaran Hyperspace during such periods of temporary insanity, though the Enclave's researchers have yet to figure out how they managed it.