Prison planet
From Tardis Wiki, the free Doctor Who reference
A prison planet was a planet used by a species, group or organisation as a prison. Some prison planets resembled prisons such as the Stormcage Containment Facility and Volag-Noc. (DW: The Infinite Quest, The Pandorica Opens). Others included the planet Dis, used by the Imperial Landsknechte during the rule of the Earth Empire as a prison due to its proximity to a sun. (NA: Original Sin) Other planets were chosen as prison planets to serve dual roles as a prison environment and sourcing a rare or useful material: New Rarga where wompom was grown and harvested and Raaga, a world rich in Tinclavic. (BNA: Ghost Devices, DW: The Visitation)
