Mars

Mars is the fourth planet in the Sol system and humanity's oldest interplanetary colony. Although the planet has a tumultuous history, it has developed into an industrial powerhouse and one of the most important worlds to the United Nations Space Command as it houses the headquarters of key military-industrial contractors such as Misriah Armory and Reyes-McLees Corporation alongside commercial megacorporations like Traxus Heavy Industries. As one of the earliest and most developed human colonies, Mars is also one of the few worlds outside Earth to have significant clout in the United Earth Government.

Phobos
For centuries, Phobos has served as the "gateway" to Mars and the planet's primary orbital port. The moon is hollowed out and almost entirely built up.

Deimos
After plans to convert the moon into a massive intrasolar cargo transport or a slower-than-light colony ship fell through, Deimos was turned into the orbital counterweight for the Tharsis industrial heavy-lift array.