The sounds of Titan   Huygens probe descending through Titan's atmosphere   On 6 June 2003, scientists gathered at the Italian Space Agency's Trapani balloon-launch facility in Sicily. To launch the 500-kilogram gondola carrying the mock-up Huygens space probe, they used a helium balloon that fully inflated to a diameter of 100 metres at its maximum altitude. When the balloon reached a height of 33 kilometres, a release mechanism opened and dropped the probe.   Huygens probe descending through Titan's atmosphere Release date: 26 October 2004