And those are Titan and Enceladus. Titan is Saturn's largest moon, and, until Cassini had arrived there, was the largest single expanse of unexplored terrain that we had remaining in our solar system.
土卫六和土卫二。土卫六是土星最大的卫星 直到卡西尼进入其轨道 这是对太阳系未知领域的 又一次重大探索