Methane rains down on Saturn's mysterious moon Titan
Saturn's moon Titan is eerily familiar and yet wholly unlike our own.
The cosmic picture: The large moon boasts a hazy atmosphere and rains methane onto its surface. Now, thanks to the long-dead Cassini spacecraft, we know that some of its lakes are more than 300 feet deep.
Background: Cassini gathered groundbreaking data on Saturn and its moons, including making a dive through the planet's rings and into its atmosphere in the final moments of its mission.
- The spacecraft flew past Titan in April 2017, when it observed the lakes, and scientists are still analyzing the treasure-trove of data it gathered and transmitted back to Earth.