Knosson was a planet in a trinary star system apparently without a native sapient species. Ral Shannon, a human ADF pilot, was marooned there when his ship crash landed after a Dalek attack. He eked out survival for three years before the Daleks returned. Defeating this second Dalek attack party gave Shannon access to the Dalek ship, and a way off the planet. However, he decided to blow up the Dalek ship and remain marooned on Knosson. This decision arguably changed Knosson's status from "uninhabited" to "population: 1".