Over the past few decades, planetary scientists have gradually added to the list of moons of our planet. solar system which may harbor inland oceans, either currently or at some point in their past. For the most part, these moons (like Europa or Enceladus) have been gravitationally linked to the gas giants Jupiter or Saturn.

Recently, however, planetary scientists have turned their attention further afield, toward the ice giant. Uranusthe coldest planet in the solar system. And now, new research based on images taken by the Voyager 2 spacecraft suggests that Miranda, a small icy moon of Uranus, may once have had a deep ocean of liquid water beneath its surface.