Dec. 14, 2006 —New research casts doubt on the existence of water near the surface of a tiny Saturn moon — a finding that, if confirmed, could set back the hunt for extraterrestrial life.
Earlier this year, the international Cassini spacecraft orbiting Saturn caused a stir when it spied what appeared to be Yellowstone-like geysers spouting from the south pole of Enceladus. Scientists speculated the eruptions were driven by shallow pools of water lurking just below the icy surface.
In an alternative view published in Friday's issue of the journal Science, other researchers propose that buried ice clathrates — not liquid water — are responsible for releasing the towering plumes through a sudden tectonic shift in the crust that causes cracks in the ice and gas to vent.
The study doesn't address whether liquid might be present anywhere else on the moon, said lead author Susan Kieffer, a planetary scientist at the University of Illinois at Urbana-Champaign, who has studied geysers on Earth and on the moons of Jupiter and Neptune.
"We didn't go into this trying to disprove liquid water," said Kieffer, adding that in her model, "there is no liquid water required."
The alternative theory shows scientists still don't really know what causes plumes to rise from Enceladus and until that's sorted out, it's premature to send a spacecraft to search for extraterrestrial life, said Bruce Jakosky, an astrobiologist at the University of Colorado at Boulder.
Jakosky noted that if liquid water is not easily accessible on Enceladus, it doesn't bode well for life.
"This would mean that Enceladus would not be a viable place for life. It makes a big difference!" he wrote in an e-mail.
