There were 7,100,000,000 stars in the known galaxy, with approximately 3,200,000,000 habitable star systems. Only about a billion of these systems have life. Only 69,000,000 of those systems meet population requirements for Imperial representation. All star systems are given coordinates that are used by navicomputers to permit space travel. To fly from the center of star system to its further limits in sublight travel, it took from 12 to 72 hours, depending on the size of said system and the potential obstacles along the way.