Underground Ocean on Titan

The first space draft to orbit planet Saturn was Cassini Huygens that was launched on 1 July 2004 to conduct a detailed study of the ringed planet and its moons. In December 2004 the Huygens probe (ESA) descended into the atmosphere of the Moon Titan, second largest moon (satellite) in our solar system.

Some on the objectives of Cassini was to find out the structure and dynamic behavior of the rings of Saturn, determine the composition of the satellite surfaces, and many more. The mission of Cassini is still ongoing. The latest strong evidence Cassini found is the evidence for ocean water beneath the frozen crust of Titan.

Prior to this scientists had suspected the presence of ocean under Titan's surface as well as Jupiters moon Ganymede, Callisto and Europa. "The evidence is strong that Titan is squishy," said planetary scientist Jonathan Lunine, with Cornell University.

According to lead author Luciano Iess, a planetary geodesist at Università La Sapienza in Rome, "Liquid water elsewhere in the solar system is one of the main goals of planetary exploration for NASA. This discovery points to the fact that many satellites in the outer solar system hide large amounts of liquid water."

The researchers focused on the powerful tides. Titan's tides faces tidal effects upto 400 times greater than our moon's draw on Earth.  It is said that the researchers montiroed how Cassini's speed altered during six close flybys past Titan between 2006 and 2011, this helped them deduced the strength of the moon's gravity field. Since a body's gravity stems from its mass, these details helped reveal how matter is distributed within Titan and how this changed depending on how near or far the moon was from Saturn during its oval-shaped 16-day orbit around the planet.

"An ocean inside Titan was expected, but it was a matter of speculation - these measurements now essentially tell you for sure there is a subsurface ocean.  It remains uncertain just how deep this ocean might be. "We cannot say if it is 10 kilometers (6 miles) or 100 kilometers (60 miles) or more. We only know that there is a liquid layer," Iess said.

This study will be published in the Journal Science.