Ocean inside Saturn's Moon

"NASA's Cassini spacecraft and Deep Space Network have uncovered evidence Saturn's moon Enceladus harbors a large underground ocean of liquid water, furthering scientific interest in the moon as a potential home to extraterrestrial microbes."

"Gravity measurements by NASA's Cassini spacecraft and Deep Space Network suggest that Saturn's moon Enceladus, which has jets of water vapor and ice gushing from its south pole, also harbors a large interior ocean beneath an ice shell, as this illustration depicts." 
Image Credit: NASA/JPL-Caltech

Reference:

http://www.nasa.gov/press/2014/april/nasa-space-assets-detect-ocean-inside-saturn-moon/#.U0b1cV6xG3F