Space & Astronomy

Cassini discovers global ocean on Enceladus

By T.K. Randall
September 16, 2015

Image: Enceladus
Credit: (PD) NASA/JPL Enceladus exhibits a slight wobble in its orbit that can only be explained if its outer shell and interior are not frozen together - something that strongly suggests the presence of a liquid ocean.

The discovery was made thanks to new research using data returned by NASA's Cassini spacecraft.

"This was a hard problem that required years of observations and calculations involving a diverse collection of disciplines, but we are confident we finally got it right," said scientist Peter Thomas.

More than seven years worth of data and photographs were used to study the moon's wobble."If the surface and core were rigidly connected, the core would provide so much dead weight the wobble would be far smaller than we observe it to be," said SETI's Matthew Tiscareno.

"This proves that there must be a global layer of liquid separating the surface from the core."

It still isn't clear what processes are stopping this ocean from freezing up however its existence opens up the door to the possibility that life may exist below the icy moon's surface.

"This is a major step beyond what we understood about this moon before, and it demonstrates the kind of deep-dive discoveries we can make with long-lived orbiter missions to other planets," said Carolyn Porco from the Space Science Institute. "Cassini has been exemplary in this regard."

Source: Astronomy Magazine

Tags: Saturn, Cassini, Enceladus