From Halopedia, the Halo wiki
Chu'ot is a large gas giant and the third planet orbiting the star Y'Deio. Eayn, the homeworld of the Kig-Yar, is the planet's primary natural satellite, though the planet itself is cold and devoid of life. Approximately the size of Neptune, Chu'ot is located within the inner region of the system's expansive asteroid belt. Several Kig-Yar colony asteroids are located close to Chu'ot, worlds inhabited by sectarian societies sustained by gray market trade. In the Kig-Yar's early history, Chu'ot held religious notability to the now-dead religions of the species. However, after the Kig-Yar joined the Covenant, the gas giant lost all cultural significance.
Chu'ot was the only known Covenant-occupied planet that humanity had cataloged before first contact with the Covenant. Its designation, according to human astrographic naming conventions, is HD 69830 d.
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