Class-M planet where an ancient civilization known as the Preservers transplanted several tribes of Native Americans centuries ago. The planet was in the midst of a dangerous asteroid belt, so the Preservers provided a powerful deflector device known as the Obelisk. The Preservers taught the tribe's medicine man how to operate this deflector, but one medicine man failed to pass that information to his son, so by 2268 the planet was defenseless against an asteroid on a collision course. Kirk and Spock of the U.S.S. Enterprise figured out how to access the deflector controls and saved the planet.