Gene Roddenberry’s classic sci-fi drama, Star Trek, made famous the warp drive, a theoretical concept whereby a spacecraft travels Faster Than Light (FTL).
I was once told by a ‘trekky’ enthusiast that the warp speeds they describe on the television shows and in the movies, may be calculated as follows. Warp factor w, from the original Star Trek series, means that the spacecraft travels at w3 times the canonical speed of light (c @ 300,000 km/s or 186,000 miles/s).3 Therefore warp factor w = 7 means the spacecraft travels at 73 = 343 c. It would be unusual to hear that the starship the USS Enterprise (see Fig. 1) had exceeded warp factor 9, which is about 729 times the speed of light.
To travel even around the local neighbourhood of our galaxy warp factor 9 (from the original TV series) just won’t do it. The nearest star to our solar system is about 4 light-years away. So travelling at warp 9, you would take 2 days to get there. Not too bad but what about to other star systems?
To travel 50 light-years, which is a very small distance in the Galaxy and which includes very few stars—only 64 Sun-like stars—would take you 25 days at this speed. Within a distance of 100 light-years from Earth there are known to be only 512 stars of the same spectral class as our sun1 and very few of those might be candidates for a solar system that could potentially support life.2 So it would be much better to be able to travel 100 light-years quite quickly but that would take you 50 days, nearly 2 months. However in the TV shows they often arrive in just a matter of hours.