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Credit: AP/PETER COSGROVE

Cassini, the most ambitious and expensive planetary expedition ever mounted, began its long trip to Saturn from Cape Canaveral, Florida, on 15 October (left). The spacecraft, which is costing the US, European and Italian space agencies $3.3 billion to build, launch and operate, will arrive at Saturn in July 2004. It will orbit the planet for four years, investigating its atmosphere, moons, rings and electromagnetic fields.

In November 2004, the European-built Huygens probe will detach from the main ship and land on the large moon Titan, taking pictures and data as it parachutes through the thick atmosphere. Huygens is the European Space Agency's first planetary lander and the first designed to touch down on the satellite of another planet apart from Earth.

As a money-saving measure, Cassini will skimp on science during the first five years of its journey to Saturn, when it will swing past Venus, Earth and Jupiter to gain velocity. Unlike the Galileo Jupiter mission, Cassini's 12 science experiments will be turned off except for a gravitational wave detection experiment and occasional instrument health checks.