Titan Artists impression of the surface of Titan the largest of Saturns moons Titan is the largest moon in the Solar System and the only one with a planetlike atmosphere Its surface is hidden by a dense blanket of orange methanerich clouds from which a continuous rain of organic compounds is thought to fall There may also be seas of liquid methane and ethane on the surface although the temperature about degrees C is too low for liquid water Scientists believe the mixture of organic compounds in Titans atmosphere might mirror that of the primitive Earth and could hold clues about the origin of life from simple organic compounds