Saturn's Death Star-looking moon may have vast underground ocean

Astronomers are reporting the best evidence yet of a vast, young ocean beneath the icy exterior of Saturn's Death Star-looking mini moon. The French-led team based its findings Wednesday on observations by NASA's former Cassini spacecraft. By analyzing changes in Mimas' orbit and rotation, the scientists have concluded that the frozen crust hides an ocean that's only 5 million to 15 million years old. The findings open up the possibility of water — and life — at seemingly sterile moons.