Editing Known Space (section)

===Hyperdrive===
[[Faster-than-light]] (FTL) propulsion, or hyperdrive, was obtained from the [[Outsider (Known Space)|Outsiders]] at the end of the First Man–Kzin War. In addition to winning the war for humanity, it allowed the re-integration of all the human colonies, which were previously separated by distance. Standard (Quantum I) hyperdrive covers a distance of one light-year every three days (121.75&nbsp;''c''). A more advanced Quantum II hyperdrive introduced later is able to cover the same distance in one and a quarter minutes (420,768&nbsp;''c'').

In Niven's first novel, ''[[World of Ptavvs]]'', the hyperdrive used by the Thrintun required a ship to be going faster than 93% of the speed of light. However, this is the only time that hyperdrive is described this way.

In the vast majority of ''Known Space'' material, hyperdrive requires that a ship be outside a star's gravity well to use. Ships which activate hyperdrive close to a star are likely to disappear without a trace. This effect is regarded as a limitation based on the laws of physics. In Niven's novel ''[[Ringworld's Children]]'' the Ringworld itself is converted into a gigantic Quantum II hyperdrive and launched into hyperspace while within its star's gravity well. ''[[Ringworld's Children]]'' reveals that there is life in hyperspace around gravity wells and that hyperspace predators eat spaceships which appear in hyperspace close to large masses, thus explaining why a structure as large as the Ringworld can safely engage the hyperdrive in a star's gravity well.

One phenomenon travelers in hyperspace can experience is the so-called 'blind spot' should they look through a porthole or camera screen, giving the impression that the walls around the porthole or sides of the camera view screen are expanding to 'cover up the outside'. The phenomenon is the result of hyperspace being so fundamentally different from normal/'Einsteinian' space that a traveler's senses cannot truly comprehend it, and instead the observer 'sees' a form of nothingness that can be hypnotic and dangerous. Staring too long into the 'blind spot' can be insanity-inducing, so as a precaution all view ports on ships are blinded when a ship enters hyperspace.