The Italian Almanac


The Ocean of Titan

The Cassini space probe has found an underground ocean on Titan, the largest and most mysterious moon of Saturn. The presence of water on Titan could mean there are conditions for life there, the Italian Space Agency (ASI) said.

''This is a scientific result of the first order,'' said ASI's space exploration chief Enrico Flamini. ''If there is water on Titan, it is important to study it to see if there are the basic conditions for the formation of organic molecules''. ASI works on the Cassini probe with NASA and the European Space Agency. The spacecraft's full name is the Cassini-Huygens probe - the surnames of two historically important astronomers.

Flamini noted that Titan was now the third body in the Solar System where a huge water mass has been found under the surface. The other two with underground oceans are Saturn's sixth-largest moon, Enceladus, and Europa, the sixth moon of Jupiter. Data from the radar were processed in Italy by Luciani Iess and Paolo Persi of Rome university. They reckon the ocean could contain minute amounts of methane and ammonia, but is ''essentially 99% water''. The probe did not actually 'see' the water under Titan's surface but basically determined it must be there because of a huge variation in Titan's movement.

The Cassini-Huygens space probe began its four-year sweep of Titan in January 2005, sending back the first data on an atmosphere resembling Earth's when life began. The probe was the first man-made device to encounter the moon - and the first to orbit Saturn. During its visit to Saturn, in which scientists have learned much more about how the Solar System formed, the probe has provided key information about what Saturn is made of. It has scanned its stormy atmosphere, molten core and mysterious rings, believed to be the remains of pulverised moons, asteroids and comets.

Titan is the primary objective of the Cassini mission because it is the only moon in the Solar System with a dense atmosphere - believed to be similar to the one initially formed when the Earth came into being. The mission will continue to study Saturn and its 31 known moons for another year.