Capella IV, also known as Ceres or Alpha Aurigae IV, is the fourth planet (4/4) in the Alpha Aurigae star system. It is rich in rare minerals Topalin. There is a medieval-like culture on the planet Capella IV with intricate customs and traditions. In 2267, the planet was invaded by the Klingons. With the help of the Federation, the attack was repulsed and the planet was declared a protectorate of the UPF.