Characteristics of the moons of Saturn


Saturn has 62 natural satellites. Here are some features of some of its moons, with mountains, valleys, and striking marks on their surfaces, often marked by asteroid bombardments causing small, huge craters.


Iapetus –  Equatorial ridge

Iapetus’s equatorial ridge was discovered when the Cassini spacecraft imaged Iapetus on 31 December 2004. Peaks in the ridge rise more than 20 km above the surrounding plains, making them some of the tallest mountains in the Solar System. The ridge forms a complex system including isolated peaks, segments of more than 200 km and sections with three near parallel ridges. 


Tethys – Odysseus crater

Odysseus is the largest crater on Saturn’s moon Tethys. It is 445 km across, more than 2/5 of the moon’s diameter, and is one of the largest craters in the Solar System.


Tethys – Ithaca Chasma

Ithaca Chasma is a valley (graben) on Saturn’s moon Tethys, named after the island of Ithaca, in Greece. It is up to 100 km wide, 3 to 5 km deep and 2,000 km long, running approximately three-quarters of the way around Tethys’ circumference, making it one of the longer valleys in the Solar System. Ithaca Chasma is approximately concentric with Odysseus crater. 


Tethys – Red arcs

Unusual arc-shaped, reddish streaks cut across the surface of Saturn’s ice-rich moon Tethys in this enhanced-color mosaic. The red streaks are narrow, curved lines on the moon’s surface, only a few miles (or kilometers) wide but several hundred miles (or kilometers) long.


Rhea – Inktomi crater

Inktomi, also known as The Splat, is a prominent rayed impact crater 47.2 kilometres (29.3 mi) in diameter located in the southern hemisphere of Saturn’s moon Rhea.


Mimas – Herschel Crater

Herschel is a huge crater in the leading hemisphere of the Saturnian moon Mimas, on the equator at 100° longitude. It is so large that astronomers have expressed surprise that Mimas was not shattered by the impact that caused it. It measures 139 kilometres (86 miles) across, almost one third the diameter of Mimas. If there were a crater of an equivalent scale on Earth it would be over 4,000 km (2,500 mi) in diameter – wider than Canada – with walls over 200 km (120 mi) high.


Enceladus – Surface with fractures

Close up of one of the ‘tiger stripes” or fissures called Baghdad Sulcus. Both heat and occasional geysers issue from this formidable crack. Some of the material coating the landscape may be snow condensed from vapor. This closeup of the surface of Enceladus on November 21, 2009, viewed from approximately 1,260 miles (2,028 kilometers) away. 


Dione – Contrasts

This image from NASA’s Cassini spacecraft shows a part of Dione’s surface that is covered by linear, curving features, called chasmata.

One possibility is that this stress pattern may be related to Dione’s orbital evolution and the effect of tidal stresses over time. This view looks toward the trailing hemisphere of Dione. 

Learn more: Iapetus, Tethys, Rhea, Mimas, Enceladus and Dione.

Images: NASA/JPL-Caltech