At first glance, Saturn’s moon Mimas appears dead and boring, with nothing to make it shine.
Other moons—such as Enceladus, Titan, and Jupiter’s Europa—harbor icy oceans, lakes of methane, or hints of habitable climates in the past. Mimas sits, apparently unchanging and unchanged. Its most common surface features are its craters, which show no obvious signs of warmth that would hint at liquid water. For decades, scientists have shrugged the moon off as a frozen ball of ice over a solid core.
