Rigel XII was a H-class world and the twelfth planet in the Rigel system. Conditions on the planet were harsh, and habitation was only possible in sealed pressure domes. Grit and dust were everywhere, and sandstorms were a frequent occurrence. The conditions were especially bad during a magnetic storm. Water was scarce, and plant life was twisted and sere.
In the 2260s, the mining operation on Rigel XII was by Ben Childress with two partners. In 2266, con artist Harcourt Mudd, using the illegal Venus drug, attempted to sell Eve McHuron, Ruth Bonaventure and Magda Kovacs to the miners. (TOS: "Mudd's Women")