We used to think moons were the boring sidekicks of the solar system. For decades, we treated them like cosmic leftovers — cold, dead rocks that did nothing but tag along with their parent planets. We ...

Far from the Sun’s heat, orbiting the outer planets of the solar system, are moons with oceans of liquid water beneath their frozen surfaces. Keith Cooper finds out how planetary scientists are ...

Add Yahoo as a preferred source to see more of our stories on Google. When you buy through links on our articles, Future and its syndication partners may earn a commission. Enceladus, a moon of Saturn ...