London, March 30 (ANI): New radar images from NASA's Cassini probe have suggested that slushy water from a hidden ocean may be pooling onto the icy surface of Saturn's moon Titan, thus bolstering the case for the existence of volcanoes on its surface.
Titan's exterior, where the temperature is around -180 degree Celsius, is thought to be mostly water-ice, but it may be a different story deep down.
Variations in the moon's rate of rotation suggest an ocean could lurk below.
An area of Titan called Hotei Arcus appears to fluctuate in brightness on timescales of several months, and in 2005, Robert Nelson of NASA's Jet Propulsion Laboratory in Pasadena, California, and colleagues, suggested this might be the result of "cryovolcanic" eruptions of water from below.
Others argued that the flickers were caused by the moon's hazy atmosphere.
The cryovolcanism idea was bolstered in 2008, when observations of Hotei Arcus by a radar instrument aboard NASA's Cassini probe revealed structures that resembled lava flows.
Some opponents of the idea still argued these might be deposits of sediment, carried by a flow of methane in the past.
Now, according to a report in New Scientist, radar images from Cassini have allowed scientists led by Randolph Kirk of the US Geological Survey in Flagstaff, Arizona, to create a 3D view of the area.
It turns out that the sinuous structures tower 200 meters above their surroundings.
They say that this is consistent with the structures having formed when slushy water and ammonia squirted onto the surface and froze, but that they could not have been produced by a flood of liquid methane depositing sediment.
The structures may have formed when slushy water and ammonia squirted onto the surface and froze.
If slush volcanoes have been erupting recently, Titan would join a select group of solar system objects - Earth and Io - known to be volcanic at present.
As for life existing in the ocean below, Kirk said, "It's conceivable life could be going on down there." (ANI)