Part of the show Plant Science, Composting and Mosquito Repellents
Space missions are fraught with potential disasters. In 2004, the Genesis mission crashed back down to earth, raising fears that its cargo of precious particles captured from the solar wind had been lost. And we all remember what happened to the Beagle mission to Mars. So hundreds of space scientists were understandably nervous as their latest baby, the comet-chasing Stardust capsule, came hurtling back to earth at 29,000 miles per hour on Sunday morning. Since it left earth in 1999, the US$212 million capsule has been on an amazing mission to brush past the comet Wild 2, which orbits out past Neptune in an area of the solar system called the Kuiper belt. Comets are rather like the clump of ice and frozen peas that you find at the back of the freezer. They are full of material that has been around since the origin of the solar system. This kind of material can tell us much about how our solar system was formed, almost like a time capsule dating back four and a half thousand million years. After a nail-biting finish, Stardust safely touched down in the Utah desert at 10:12 GMT on Sunday. Stardust has travelled an incredible three billion miles on its epic voyage, and was sent to within 149 miles of the comet's core. Using special tennis-racket shaped collected filled with aerogel - an incredibly light substance - Stardust picked up tiny particles shaken off by the comet as it hurtled through space. The capsule has been transported to NASA's Housten Space Centre for opening, but around 150 scientists all over the world be be able to study the spacedust inside. This includes Professor Monica Grady at the Open University (link to Monica's show) and researchers at Imperial College, London. They will asking many questions, such as whether comets could have deposited the water essential for life onto the earth's surface.