London: An ocean of water may lie beneath the surface of Titan, Saturn's largest moon, indicating that it could have aliens, astronomers said. According to new data from the Cassini-Huygens spacecraft, Titan is now the fourth object in the solar system with a deep ocean, after Jupiter's moons Ganymede, Callisto, and Europa.

Dr Ralph Lorenz and his colleagues of the Applied Physics Laboratory in Maryland analysed Cassini radar observations since 2004 and found that some of the geological features on the moon's surface had drifted from a fixed reference point, implying that the moon's rotation speed had temporarily increased.

This was in consonance with previous models of the winds in Titan's dense atmosphere which may be rocking it back and forth around its axis, speeding then slowing its rotation speed. The observed shifts seem large enough that Titan's crust and core have to be separated by a liquid ocean in order to allow the atmosphere to move the crust around. It is buried under several tens of kilometres of ice, the Daily Telegraph reported.

This internal ocean is predominantly water, probably with a few percent of ammonia acting as an antifreeze, said Dr Lorenz. Tides are present on Titan and it is thought that the lakes of liquid hydrocarbons on the surface probably go up and down a meter or two every Titan orbit of 16 days, though whether this causes so called tiding heating is not clear, he added.

Titan is understood as a mysterious place with a thick atmosphere rich in organic compound and the building blocks of life, with a dense atmosphere similar to that of the primordial Earth, lakes of liquid methane near its north pole, and nitrogen clouds.

Source : UNI