An ocean within Saturn's "Death Star moon"

What they found: Data from the final days of the Cassini mission studying Saturn and its moons revealed a tell-tale "oscillation" in the rotation of the moon that typically indicates an ocean within it, according to a new study in the journal Icarus.

• Mimas, however, doesn't look like other worlds that likely harbor oceans beneath their crusts.
• Worlds like Europa and Pluto tend to have surface features — like cracks and other geological markers — but Mimas doesn't outwardly appear to have any of those signs on the surface.
• "If Mimas has an ocean, it represents a new class of small, 'stealth' ocean worlds with surfaces that do not betray the ocean’s existence," Alyssa Rhoden, one of the authors of the new study, said in a statement.
• According to computer modeling done by the research team, Mimas appears to have a shell of ice 14–20 miles thick covering the ocean.

Yes, but: This new evidence may make scientists rethink what they understand of Mimas' evolution, possibly changing how they see other objects in the solar system as well.

• If Mimas is an ocean world, it could help researchers learn more about whether other moons in the solar system, especially Uranus' moons, might have oceans within them, according to Rhoden.