Saturn’s second-largest moon, Rhea, could be the first known moon with rings. The spacecraft Cassini detected apparent evidence of rings when it spotted debris around Rhea as it flew by in 2005, reports space.com. The set of rings has not been directly seen, but scientists inferred that the rings existed because the spacecraft measured a drop in electrons on both sides of the moon.
Rhea, which is about half as large as Earth’s moon, is one of Saturn’s dozens of moons. “Rhea seemed to be one of the least interesting of the moons, but now it looks like it might be interesting for its own special reasons,” said a Cassini scientist . Researchers hope to get a closer look at the moon if the spacecraft’s mission is extended. (Read more deep space stories.)