POPULATION: ~17 million (pre attack)
Sigma Octanus IV is a human inner colony world, and the location for the Battle of Sigma Octanus IV in 2552. The battle is notable for being one of the rare victories for the UNSC in space, using unconventional tactics to defeat the Covenant invasion forces. Covenant forces were still able to make landfall during the attack, causing serious damage to civilian centers such as Côte d'Azur. During the Covenant surface invasion, they discovered a Forerunner artifact which contained the location of Alpha Halo. Sigma Octanus IV is also known for being the homeworld of Spartan-II lead trainer Franklin Mendez.