Dione, the fourth-largest moon of Saturn (and the 15th largest moon in the Solar System) hangs in front of the gas giant and its icy rings. This photo was captured on August 17, 2015 during Cassini’s final close flyby of the icy moon. North on Dione is up. The image was obtained in visible light at a distance of approximately 45,000 miles (73,000 kilometers) from Dione.
It has probably a huge ocean, under an icy shell, like Enceladus, which is buried about 60 miles (100 kilometers) beneath the shell. Image source: NASA