A
cryovolcano (colloquially known as an
ice volcano) erupts slurries of volatile compounds such as water or methane instead of lava. These substances are usually liquids and form plumes, but can also be in vapour form. After eruption, cryomagma condenses to a solid form when exposed to the very low surrounding temperature. Cryovolcanoes form on icy moons, and possibly on other low-temperature astronomical objects (e.g., Kuiper belt objects).
The energy required to melt ices and produce cryovolcanoes usually comes from tidal friction. It has also been suggested that translucent deposits of frozen materials could create a sub-surface greenhouse effect that would accumulate the required heat.
Ice volcanoes were first observed on Neptune's moon Triton during the Voyager 2 flyby in 1989.
On November 27, 2005 Cassini photographed geysers on the south pole of Enceladus.
Indirect evidence of cryovolcanic activity was later observed on several other icy moons of our Solar System, including Europa, Titan, Ganymede, and Miranda. Cassini has observed several features thought to be cryovolcanoes on Titan. Such volcanism is now believed to be a significant source of the methane found in Titan's atmosphere.
In 2007, observations by the Gemini Observatory showing patches of ammonia hydrates and water crystals on the surface of Pluto's moon Charon suggested the presence of active cryovolcanoes/cryo-geysers
-Content taken from
wikipedia