The Horus system is a planetary system in the United Empire of Earth (UEE) that consists of an M-type main sequence star, two terrestrial planets, a super-Jupiter, and two asteroid belts. In SEY 2528, navjumper Marie Sante reported her discovery of the Horus system to the United Planets of Earth (UPE), alongside detailed documentation describing its celestial bodies. It was incorporated into the Perry Line when Sante discovered a jump point to the Xi'an-owned R.il'a system in 2542, after which the UPE closed Horus to non-military personnel.
When the Perry Line was dissolved in 2793, the UEE government re-opened the system and oversaw the colonization of the tidally-locked planet Serling (Horus I). Horus' connection to the Xi'an Empire, once a hindrance to its development, is now the main driver of its economic growth.