Saturn – one of the largest planets in our solar system and one of those furthest away from Earth. Among its numerous satellites is the aptly-named Titan, Saturn’s largest moon. It was discovered in 1655 by the Dutchman Christiaan Huygens. Titan is the second-largest moon in the solar system and is believed to be the only one with an atmosphere, which is why scientists are so interested in it.The Cassini-Huygens mission – a joint operation between the US’s NASA and the European Space Agency – was launched in 1997 from Cape Canaveral in Florida. It is the largest interplanetary spacecraft ever built. Its aim is to study Saturn, its rings, its moons and its atmosphere. In December, Cassini dropped off Huygens on its journey towards Titan, which has now culminated in the probe’s successful landing on the moon’s surface. Huygens is the first probe ever to land on a world in the outer solar system. Scientists believe Titan could be storing information that could explain how life came to Earth – rather like taking a four-billion-year trip back in a time-machine. Astronomer Louis Michel says: “There’s a special kind of chemistry on Titan which we believe has followed a certain type of evolution and has led to the formation of large molecules, some of which have signs of life. That’s what we’re interested in, we want to understand the relation between the primitive object, its evolution and the emergence of life. The way Titan was formed will give us information on how the earth was formed.” The probe’s seven-year journey in space has culminated in success for NASA and ESA. Scientists now have to piece together all the data, images, measurements and sounds that are being beamed back to Earth, with the hope of discovering a little bit more about where we come from.