Titan is the largest moon of the planet Saturn, and the second largest moon in the solar system. It's bigger than Mercury! Given that size, it's not surprising that its surface would show a lot of different environments, as varied in some ways as Earth itself.
Still, there any many amazing features detected on Titan, including dunes, mountains, cryovolcanoes, and valleys, Shockingly, Titan also has dozens of huge lakes of liquid methane and ethane near its north pole! These were found by the Cassini spacecraft, which orbited Saturn for 13 years, and made many close passes of Titan. This was a huge discovery, the only body other than Earth known with open stable liquid on its surface.
Cassini also saw tributaries feeding into these lakes, indicating that the frigid moon (around -180°C) has a methane cycle like Earth's water cycle, with methane evaporating off the lakes, raining out in the highlands nearby, then flowing back into the lakes.
A mosaic of Titan’s north pole from Cassini near infrared observations, assembled by Kevin McGill. Credit: NASA/JPL-Caltech/SSI/CICLOPS/Kevin M. Gill
And now new results looking at old Cassini data have revealed another startling aspect of some of these lakes: They have rough seas. ...