Cassini Finds Likely Subsurface Ocean on Saturn Moon
Data from NASA’s Cassini spacecraft have revealed Saturn’s moon Titan likely harbors a layer of liquid water under its ice shell. Researchers saw a large amount of squeezing and stretching as the moon orbited Saturn. They deduced that if Titan were composed entirely of stiff rock, the gravitational attraction of Saturn would cause bulges, or solid “tides,” on the moon only 3 feet in height. Spacecraft data show Saturn creates solid tides approximately 30 feet in height, which suggests Titan is not made entirely of solid rocky material. The finding appears in today’s edition of the journal Science.
The presence of a subsurface layer of liquid water at Titan is not itself an indicator for life. Scientists think life is more likely to arise when liquid water is in contact with rock, and these measurements cannot tell whether the ocean bottom is made up of rock or ice. The results have a bigger implication for the mystery of methane replenishment on Titan.