Scientists used to think that Uranus and its big moons were like boring, dead planets.
But now, they think they might have oceans hidden under the surface, which could be a good place for life to live!
A spacecraft called Voyager 2 flew past Uranus a long time ago, but it was during a big storm from the sun, so it didn't show us the real picture.
NASA is planning to send another spacecraft to Uranus to learn more about these exciting moons.
