Icy Moons
Known icy moons belong to giant planets, whose orbits lie beyond the Solar Systems frost line. An additional requirement is that a moon did not form in the inner region of a proto-satellite disk, which is too warm for ices to condense.
Jupiter's Io is anhydrous and likely has an interior of rock and metal. Europa is thought to contain 8% ice and water by mass with the remainder rock. Jupiter's outer two Galilean moons Ganymede and Callisto contain more ice since they formed further from the hot proto-Jupiter.
Saturn's moon Titan looks and behaves more like Earth than any other body in the Solar System. Titan is known to have stable pools of liquid on the surface.
-
Europa is believed to have a subsurface ocean
-
False-color image of Ganymede
-
Callisto showing frost deposits
-
Titan showing surface and atmospheric details
-
Plumes above the limb of Enceladus
-
A potential frost deposit on Umbriel
-
A cloud over the limb of Triton
Read more about this topic: Icy Moon
Famous quotes containing the words icy and/or moons:
“And even my sense of identity was wrapped in a namelessness often hard to penetrate, as we have just seen I think. And so on for all the other things which made merry with my senses. Yes, even then, when already all was fading, waves and particles, there could be no things but nameless things, no names but thingless names. I say that now, but after all what do I know now about then, now when the icy words hail down upon me, the icy meanings, and the world dies too, foully named.”
—Samuel Beckett (1906–1989)
“Since moons decay and suns decline,
How else should end this life of mine?”
—John Masefield (1878–1967)