Heritage

Heritage was a mining planet, chiefly known for its production of Thydonium. It had multiple moons and suns.

In the mid-61st century the Federation marketed it as "luxurious", and claimed that it was possessed of a "state of the art" living environment. Their marketing language would prove not just deceptive, but downright ironic. By 6048, the last new resident of the colony was at least 20 years in the past and even visitors were exceedingly rare. The human colony had, for all intents and purposes failed by the time the Seventh Doctor and Ace visited. (PDA: Heritage)