Ectanus 45 was acting as a frontline support system for the UNSC's war effort in 2535 due to the destruction of most of the Outer Colonies. One of the planets in the system is Chi Rho, which had Vice Admiral Jean Mawikizi in command. Jacob Keyes was assigned to UNSC Midsummer Night from this system.
- Halo: The Cole Protocol (First appearance)
- Halo: Fractures - Extraordinary Tales from the Halo Canon
- Into the Fire