The Zeta Doradus system is a planetary system near UNSC-controlled space, approximately 38 light-years from Sol. It contains many planets orbiting the star Zeta Doradus, almost all of which are icy rocky planets or gas giants, none of which are habitable. The one exception, however, is the artificial planet known as Onyx.
- Dorado is an actual constellation, and it does possess a Zeta Doradus within it.
- Office of Naval Intelligence//Section 3 has a file involving this system which is labeled XF-063. It shows information about the star Zeta Doradus: Diameter, satellites, gravity, atmosphere, surface temperature, local day and local year of the planet.