Titan is Saturn’s moon with a thick atmosphere and lakes of liquid methane and ethane on its surface.
Titan is the second-largest moon in the Solar System and the only moon known to have a dense, nitrogen-rich atmosphere. Its surface pressure is about 1.5 times Earth’s sea-level pressure, while its surface temperature is approximately −179 °C. At that extreme cold, methane and ethane can behave as liquids.
Clouds, rain, rivers, lakes, and seas create a methane-based cycle that resembles Earth’s water cycle. Radar observations from NASA’s Cassini spacecraft revealed extensive polar lakes and seas, especially in Titan’s northern region. The Huygens probe landed on Titan in 2005, becoming the first spacecraft to land in the outer Solar System.
Titan is not the only Saturnian moon with striking geology. Enceladus ejects water-rich plumes from a subsurface ocean, whereas Titan’s distinctive feature is its thick atmosphere and surface hydrocarbon lakes.