The largest moon of Saturn is Titan. Titan is notable for its dense atmosphere, which is primarily composed of nitrogen, with clouds and possibly rain of methane and ethane. Its thick atmosphere makes it unique among moons in the solar system. Titan's surface features rivers, lakes, and seas of liquid methane and ethane, making it an intriguing subject for astrobiological studies. Approximately 3,200 miles in diameter, Titan is larger than Mercury and has a complex system of organic chemistry, leading scientists to explore its potential for hosting life in its subsurface ocean.