Icy moons are a class of natural satellites with surfaces composed mostly of ice. An icy moon may harbor an ocean underneath the surface, and possibly include a rocky core of silicate or metallic rocks. It is thought that they may be composed of ice II or other polimorph of water ice.[1] The prime example of this class of object is Europa.
Icy moons warmed by tides may be the most common type of object to have liquid water,Template:Citation needed and thus the type of object most likely to have water-based life.Template:Dubious
Some icy moons exhibit cryovolcanism, as well as geysers. The best studied example is Saturn's Enceladus.
Orbits[]
All known icy moons belong to giant planets, whose orbits lie beyond the Solar System's 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.
Europa is thought to contain 8% ice and water by mass with the remainder rock.[2] 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.[3] Titan is known to have stable pools of liquid on the surface.[3]
Images[]
References[]
- ↑ Chaplin, Martin (2007-10-26). Ice-two structure. Water Structure and Science. Retrieved on 2008-01-02.
- ↑ Canup, Robin M.; Ward, William R. (2008). "Origin of Europa and the Galilean Satellites". Astrophysical Journal.
- ↑ 3.0 3.1 Rosaly Lopes and Robert M. Nelson (2009-08-06). Surface features on Titan form like Earth’s, but with a frigid twist. IAU. Retrieved on 2009-12-21.
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