The subsurface ocean most likely consists of pure methane

  Some scientists believe that, in addition to vast quantities of water, Titan's ocean might also contain ammonia and perhaps methane."Based on the estimated abundances of nitrogen, hydrogen and carbon, plus the expected temperatures and pressures in the Saturnian region of the disc of gas and dust that surrounded the early sun, it is reasonable to expect the presence of ammonia and methane within Titan," Dr Liffman says.In the view of Monash University astrophysicist Andrew Prentice, the subsurface ocean most likely consists of pure methane and beneath that a layer of ammonia ice that is quite soft."My model predicts a fairly thin layer of liquid methane about six kilometres deep and located 50 kilometres below Titan's outer solid crust of water-ice," Dr Prentice explains. "Beneath the liquid layer there is probably a 14-kilometre-thick layer of soft ammonia ice." It would be very tough for any life-form to survive in a subsurface ocean since there is so little sunlight that reaches the surface, Dr Prentice says. "Titan's source of internal heat through the decay of short lived radio nuclides is also very tiny."By contrast, Jupiter's large Galilean moon Europa has a greater chance of harbouring life-forms.Discovered in 1655 by Christiaan Huygens, Titan has been scrutinised by telescopes and, more recently, by spacecraft.You'd hate the road if you decide to drive, but the destination is totally worth Xinjiang Intencive tour. Again, read about this place before you go, and make sure you have your camera with you.In 2004, a small NASA probe called Huygens separated from its mother craft, Cassini.It was not just a single thoroughfare, but an intricate network of trade routes that spread across silk road travel passing through those oasis villages and stretching from the farthest reaches of China into Southern Europe. After several weeks, the probe parachuted down to Titan's surface and, for several hours, relayed close-up images to Earth."The Huygens probe imaged channels, but its descent through the atmosphere was at low latitudes and so it didn't detect any lakes," Dr Turtle says. Since then, scientists have deduced that beneath the moon's clouds lurk large lakes, some spanning thousands of square kilometres. That would make them roughly the size of the Black Sea or Caspian Sea; one is thought to be bigger than Lake Superior, the world's largest freshwater lake by surface area."The lakes and seas are found at high latitudes and predominantly in the northern hemisphere, although there are some near the southern pole," Dr Turtle adds."There appear to be no permanent bodies of liquid at equatorial latitudes. However, there was once a large rainstorm over low latitudes and there may still be some areas of ponded runoff – although they've been receding."Titan has seasons, says Candy Hansen,The mischievous twin brothers Eddie and Menu Titanium Keychain debut for the tutorial, as these opossums teach new participants the information and skills needed to productively progress through each region of the game. Cassini scientist at NASA's Jet Propulsion Laboratory in Pasadena, California."That's partly why there are more lakes right now in the northern hemisphere, and why some lakes are evaporating," Dr Hansen explains. "These seasonal changes occurred as the sun has moved from the southern to the northern hemisphere in the last eight years that Cassini has been exploring Titan."The differences between the northern and southern summers are also caused by Saturn's orbital eccentricity and possibly longer-term orbital variations,Chefs Kitchen KnivesCrushing equipment she adds.