by Catherine Griffin
February 22, 2013
from ScienceWorldReport Website




(Photo : NASA/JPL-Caltech/Space Science Institute)

NASA has announced that Saturn's moon, Titan, may possess a subsurface ocean.

The colorful globe of Saturn's largest moon passes in front of the planet and its rings

in this true color snapshot from NASA's Cassini spacecraft.



It's not only Jupiter's moon that may harbor a subsurface ocean, NASA has announced that Saturn's moon may also possess a layer of liquid water under its icy shell.


Data from the organization's Cassini spacecraft has revealed the new findings.


The findings, published in the journal Science, examined data taken by Cassini of Saturn's moon, Titan, during six close flybys.


The largest of Saturn's moons, Titan rotates the planet every 16 days. Researchers studied the moon's shape during different parts of this orbit. Because Titan is not spherical and is instead slightly elongated like a football, its long axis grew slightly when it was closer to Saturn. When it was further away from its home planet, though, the moon became nearly round in shape.


Cassini was able to measure the gravitation effect of this squeeze and pull that researchers observed.


So what exactly caused this alteration in Titan's shape?


Subsurface tides could certainly be an explanation - similar to the ones found on Jupiter's moons. An ocean layer does not have to be huge or deep to create these tides. A liquid layer between the external shell and a solid mantle would allow Titan to bulge and compress as it orbits Saturn.


Because Titan's surface is actually mostly made of water ice, it would certainly make sense that Titan's subsurface ocean is mostly liquid water.


While this water may not be an indicator of life on the moon, it could explain the methods for methane replenishment on Titan.


A liquid ocean beneath Titan's surface that is peppered with ammonia could produce ammonia-water liquids that bubble through the moon's crust and liberate the trapped methane in surface ice.

"The presence of a liquid water layer in Titan is important because we want to understand how methane is stored in Titan's interior and how it may outgas to the surface, said Jonathan Lunine, a Cassini team member, in a press release.


"This is important because everything that is unique about Titan derives from the presence of abundant methane, yet the methane in the atmosphere is unstable and will be destroyed on geologically short timescales."

Check out the video below, courtesy of NASA, to see an artist's concept of the "tides" on Titan: