Pazithi Gallifreya was one of two moons orbiting the Time Lord homeworld of Gallifrey. Its coppery shine was visible even during the day. It was heavily industrialised by the Gallifreyans for smelting purposes.
The moon had the highest concentration of Taranium in the universe. The Time Lords mined it for their temporal technology, such as the Time Scoop.
Ancient Gallifreyans worshipped it as a virgin goddess. (PROSE: Cat's Cradle: Time's Crucible)
Pazithi Gallifreya was caught in one of Gallifrey's atmospheric flares and destroyed as the Eighth Doctor destroyed Gallifrey at the end of the War. (PROSE: The Gallifrey Chronicles)