Buwan

Buwan is the primary natural satellite orbiting the planet Balaho, the homeworld of the Unggoy. Located in the Tala system, Buwan orbits Balaho alongside the planet's secondary moon Padpad.
Along with Padpad, Buwan was mined extensively in order to feed the assembly forges of the Holy City of High Charity. The moon was the site of a Covenant hydro-processing center that harnessed Buwan's waters to refuel capital ships.