It was likely part of the Tethys Ocean, the researchers say, an ancient sea from the time of the Pangaea supercontinent. 

This week, satellites spot Earth’s fastest-growing city, young stars gleam through clouds of dust, and Saturn’s moon Tethys shows off its literally epic scar.

In this photo, Tethys looks as if it’s hanging from Saturn’s A ring and its skinny, outer F ring.