Ceres

Ceres was a minute dwarf planet located in The Asteroid Belt separating Mars from Jupiter. It was home to the two-class system of the Master and the Scribe aswell as the psychic mineral, Cerulium which possessed the ability to inhibit free will. The Masters incorporated Cerulium into bracelets and used them to control the Scribes which they would use as slaves. Eventually a symbiotic relationship developed between the two; The Master was enchanted by the Scribes who had no thought but to compliment and assist the Master. They were so amused with one another that they were oblivious to the threat of an incoming asteroid which destroyed their civilization. Chunks of Cerulium remained, some one which one of these came to Earth in 2050 and were used by Inspector Drake in his plan to create a mindless population of obedient drones however K9 destroyed all the bracelets and foiled the plan. (K9TV: Sirens of Ceres)

Although Ceres was never referred to as being the same Ceres as the dwarf planet located between Mars and Jupiter, it most likely was, as it's closer distance to Earth would make it more possible for the Cerulium to arrive.