moons
Saturns largest moon, Titan, is about one and a half times the size of Earths moon. Titan is even larger than the planet Mercury. The picture below compares the size of Titan to Earth Figure below . Scientists are very interested in Titan. The moon has an atmosphere that is thought to be like Earths first atmosphere with nitrogen and methane. This atmosphere was around before life developed on Earth. Like Jupiter's moon, Europa, Titan may have a layer of liquid water under a layer of ice. Scientists now think that there are lakes on Titan's surface. Don't take a dip, though. These lakes contain liquid methane and ethane instead of water! Methane and ethane are compounds found in natural gas.