In a few weeks, after a seven-year journey across the solar system, a robot spacecraft bristling with British instruments will plunge into the atmosphere of the mysterious, methane-shrouded world of Titan. The mission is one of the most ambitious ever undertaken by space engineers. If successful, it will provide precious information about a world regarded as a remote, frozen version of early Earth and could lead to new understanding about life's evolution on our planet. But if the £250 million probe is lost, scientists will suffer a setback unprecedented by even their own high-risk standards. Many have worked on the mission - named after the astronomer Christiaan Huygens - for half their working lives. Failure would be devastating. 'This is not like the planet Mars, where we can return every couple of years,' said John Zarnecki, Britain's key Huygens scientist. 'Titan - the largest moon of Saturn - is very, very far away. This is going to be our only shot at it for an extremely long time.' Zarnecki has already spent 16 years working on a mission which, so far, has survived its two billion-mile journey unscathed, though things will get much hotter when it reaches its last 100 miles. As it touches Titan's atmosphere, the probe will have to slow from 15,000mph to 10mph. This will be achieved using a heat shield and then parachutes which have been travelling through freezing space since 1997. 'I was calm until a few weeks ago, then I started waking in the night in a cold sweat,' said Zarnecki, an Open University physicist.
View: Full Article | Source: The Observer
