Changes

; LY, light year: The distance traveled by light in one Earth year. Light travels at 300,000 km/sec, so a light year is [1 light year = 9.4605284 × 1015 meters]. One light second - 300,000 km or the distance light travels in one second

; FTL: faster than light.

; FTL drive: the drive that enables ships to cross interstellar distances fast than light would (so in a relatively short time)