Pluto May Have Had an Underground Ocean

 Pluto's giant moon, Charon, may carry cracks indicating that the icy body once had an underground ocean, reveals NASA in a latest release.

The icy world Pluto, which is an extremely distant world orbiting the sun more than 29 times farther than Earth, is said to have an environment that is extremely cold (-222 degrees Celsius) to allow liquid water on its surface. And its moons are in the same frigid environment. But a new NASA funded study says that the planet's moon might have had a warmer temperature that supported the presence of flowing water. The scientists say this based on the theory that the moon might be carrying cracks on the surface going by available evidence, which indicates that the celestial body may have housed an underground ocean earlier.

"Our model predicts different fracture patterns on the surface of Charon depending on the thickness of its surface ice, the structure of the moon's interior and how easily it deforms, and how its orbit evolved," said Alyssa Rhoden of NASA's Goddard Space Flight Center in Greenbelt, Maryland. "By comparing the actual New Horizons observations of Charon to the various predictions, we can see what fits best and discover if Charon could have had a subsurface ocean in its past, driven by high eccentricity."

Prior to this, scientists have found evidence of water on Jupiter's moon Europa and Saturn's moon Enceladus. Now they assume that it is the oval-shaped orbits (eccentric) that generated large tides on Charon's surface in the past that caused friction eventually leading to the formation of fractures.  It is the tidal heating that extended the lifetime of subsurface oceans on Europa and Enceladus by maintaining warm temperatures in the interior.

"Depending on exactly how Charon's orbit evolved, particularly if it went through a high-eccentricity phase, there may have been enough heat from tidal deformation to maintain liquid water beneath the surface of Charon for some time," said Rhoden. "Using plausible interior structure models that include an ocean, we found it wouldn't have taken much eccentricity (less than 0.01) to generate surface fractures like we are seeing on Europa."

Telescopic observations reveal that Charon's orbit is currently in a stable state. In this current orbit Charon is not expected to produce any significant tides, hence, the ancient underground ocean currently may be frozen.

One of the key ingredients for known forms of life is liquid water and the oceans of Europa and Enceladus are places where extraterrestrial life may be found.  The scientists are still working to evaluate whether or not these oceans had other key elements such as carbon, nitrogen and phosphorus. It is unclear whether the oceans existed long enough for life to form.

Rhoden added, "This research gives us a head start on the New Horizons arrival - what should we look for and what can we learn from it. We're going to Pluto and Pluto is fascinating, but Charon is also going to be fascinating."

NASA's New Horizon spacecraft will visit Pluto in  July 2015, and observers will then get more details about its environment then.

The finding was documented in Icarus.