spacetoday.net: Enceladus jets may be linked to liquid water

Posted: Thu, Nov 27, 2008, 11:31 AM ET (1631 GMT)
Cassini flyby of Enceladus illustration (NASA)

Jets of dust and gas ejected from the Saturnian moon Enceladus may be generated by liquid water below the moon's icy surface, a finding that has astrobiological implications. Scientists used data from two Cassini flybys of Enceladus in 2005 and 2007 to measure the density of waver vapor in plumes emanating from the surface, finding that the plumes were nearly twice as dense in 2007 than two years earlier. That discovery contradicts a leading explanation for the plumes, where tidal forces from Saturn create new vents; Enceladus was farther from Saturn in 2007 and hence the tidal forces were weaker. The observations do support an alternative model for the plumes, where the vents channel water vapor from a warm source, most likely liquid water, below the surface. The existence of liquid water would mean that Enceladus would have all the key ingredients needed to support life.