New York Times
: Beneath the surface of Saturn’s moon Enceladus probably lies a sea of water at least as large as Lake Superior, according to David Stevenson of Caltech and colleagues, whose findings
appear today in Science
. Although NASA’s Cassini
spacecraft, which has been collecting data since it arrived at Saturn in 2004, can’t directly detect subsurface water, a series of flybys have allowed the researchers to study the moon’s gravity field and infer its interior structure. An anomaly between the amount of mass detected at the surface of Enceladus's south pole and the pull of gravity indicated that there must be something more massive than ice there to compensate. “The natural candidate is water,” said Stevenson. And if there is a sea of warm water on Enceladus, it will be the most likely place to look for the presence of extraterrestrial life.