Volcanically active worlds
In our solar system there are few known volcanically active worlds - bodies where openings in the surface crust allow material to forcefully escape, often in spectacular showers of ash, rock or gases. To witness such a display you would have to visit parts of Earth, Io, Triton or, perhaps, Enceladus.
Volcanoes on Earth are generally found at the boundaries of tectonic plates, such as around the Pacific Ring of Fire. Earth is the only planet in the solar system which contains these forces - others, such as Mars, are 'dead' worlds where volcanic activity has long since ceased. To witness extra-terrestrial volcanic activity, you would need to visit Io or Triton, moons orbiting Jupiter and Neptune respectively. However, it has recently been suggested that Enceladus, one of Saturn's moons, might also be volcanically active - this could explain the icy geysers in the southern region of this tiny world, first observed in 2005 by the Cassini probe. If it is true that this little moon is spewing water into space,[1] Enceladus would be added to the growing list of places in the solar system that might be home to some form of life. To try to resolve these matters, Cassini is on course for a return visit to Enceladus, timed for March 2008.[2]
Footnotes
- ↑ Science@NASA: 'Radical! Liquid Water on Enceladus'. 3rd September 2006.
- ↑ New Scientist: 'Geyser teaser: the moon that should be colder'. 25th August 2007. Requires subscription for the full article.
External links
- Cassini-Huygens Home - official website covering this joint NASA/ESA/ASI mission
- Multimedia - Images -Moons - Enceladus - Cassini photos of Enceladus, with NASA information