See 14 Mind-Blowing Places in Our Solar System

Saturn’s moon Titan is arguably the most alien place in the solar system, with its thick atmosphere, hydrocarbon seas, giant dust storms, ice volcanoes, and precipitation in the form of raining methane and ethane. In 2013, NASA’s Cassini spacecraft spotted a 100-square-mile (260 square km) island-like geological formation in Ligeia Mare, one of Titan’s largest seas. Previous scans showed no signs of this feature, and it proceeded to disappear over the next several months. And then it appeared again.

Scientists aren’t entirely sure what it is, citing such possibilities as waves, bubbles, floating solids, and suspended solids (like silt in a terrestrial delta). Also, because Titan was transitioning from spring into summer at the time of the observations, scientists believe the phenomenon is tied to the change of seasons. Like I said, Titan is a very alien place.