This image, captured by Cassini’s wide-angle camera, was photographed when the mission was 40,000 miles (65,000 km) from Tethys, and Saturn and its rings can be seen in the background.
This image shows the Saturn’s icy moon Tethys. Image credit: NASA / JPL-Caltech / Space Science Institute.
NASA’s Cassini orbiter took this incredible image of Tethys on November 23, 2015.
The icy moon appears to float between two sets of gas giant’s rings, but it’s just a trick of geometry.
The rings, which are seen nearly edge-on, are the dark bands above Tethys, while their curving shadows paint the planet at the bottom of the image.
Tethys, Saturn’s fifth largest moon, is a cold and heavily scarred body, about 662 miles (1,066 km) in diameter.
It was discovered in March 1684 by the Italian astronomer Giovanni Domenico Cassini.
This moon has a surface composed mostly of water ice, much like Saturn’s rings.
Water ice dominates the icy surfaces in the far reaches of our Solar System, but ammonia and methane ices also can be found.
Tethys has two impressive features: a huge crater and a great canyon.
The 280-mile-wide (450 km) impact crater Odysseus dominates the western hemisphere of the moon, covering 18 percent of its surface area (a comparably sized crater on our planet would be as large as Africa).
The second feature is a long canyon called Ithaca Chasma. It is around 60 miles (100 km) wide, 2-3 miles (3-5 km) deep, and extends 1,200 miles (2,000 km).
Some scientists suggest Ithaca Chasma may have been caused by expansion of internal liquid water as it froze into ice after the surface had already frozen.
Tethys’ surface temperature is minus 305 degrees Fahrenheit (minus 187 degrees Celsius).
