Après Encelade: Thetys et Dione ont un cryovolcanisme

http://www.postchronicle.com/news/science/article_21286309.shtml

Two Of Saturn's Moons Found To Be Active
By Staff
Jun 13, 2007

The European Space Agency said astronomers have discovered that Saturn's moons Tethys and Dione are flinging massive streams of particles into space.

The ESA said the finding from data derived from the Cassini spacecraft suggests the possibility of some sort of geological activity, perhaps even volcanic, on the icy moons.



Until the discovery, only Enceladus among Saturn's inner moons was known to be an active world, with huge geysers spraying gases hundreds of miles above the moon's surface.

"This new result seems to be a strong indication that there is activity on Tethys and Dione as well," said Andrew Coates from the Mullard Space Science Laboratory at University College London.

Such activity is of interest to planetary scientists since it suggests the planet has yet to reach equilibrium or is perhaps being supplied with energy.

The findings are reported in the journal Nature.

The Cassini-Huygens mission is a cooperative project of the ESA, the National Aeronautics and Space Administration and the Italian Space Agency. (c) UPI