Sol
From Halopedia, the Halo wiki
Sol, also known as the Sun, is the main star in the Sol System. It is an average sized star in its main sequence phase, and is the dominant source of light for Earth. According to current definitions, eight planets and 5 dwarfs planet orbit it, for a total of 12, including the four inner terrestrial planets and the four gas giants, separated by an asteroid belt. Many smaller planetoids also orbit sol, and many of the systems planets possess moons of varying size and number.