Tethys
Saturn’s bright moon is home to some of the most impressive surface features in the Solar System © JPL; NASA Arguably the standout feature on Tethys is the Odysseus impact basin, a 450-kilometre (280-mile) wide hole – nearly half the moon's diameter. It is thought to have been created by a massive impact over three billion years ago, which may also have formed the 2,000-kilometre (1,242-mile) long valley called Ithaca Chasma.
Tethys’s albedo, or surface reflectivity, differs on either hemisphere, which shows up in this enhanced colour image taken by the Cassini spacecraft at a distance of about 53,000 kilometres (33,000 miles): the leading side on the right is bombarded by charged particles from Saturn’s radiation belt, changing the chemical composition of the surface material. On the trailing side,…