While the rest of the moon appears dark, the photo shows a 280-mile impact region called Odysseus, spanning near half the width of the entire moon.
"With the expanded range of colors visible to Cassini's cameras, differences in materials and their textures become apparent that are subtle or unseen in natural color views," NASA said.
Scientists believe the different coloration on Tethys could indicate differences in the composition or structure of the area exposed by the impact crater. While Tethys is believed to be largely water and ice, Odysseus isn't the first standout characteristic of the moon to be pique the interest of scientists.
The satellite also has a long canyon called Ithaca Chasma, which is believed to have formed when the moon colled and cracked the moon's outer crust, according to NASA.
Launched in 1997, the Cassini mission arrived in the Saturn system in 2004 where it has been working ever since to study the gas giant and its dozens of moons. The probe's mission is scheduled to end in September 2017 when it will make a fatal plunge into Saturn's atmosphere.