Huygens probe at Titan. Artist's impression of the Huygens probe entering the atmosphere of Titan, the largest moon of Saturn. Huygens will enter the nitrogen and methane atmosphere of Titan travelling at 21,960 km/h. The probe will take about three minutes to slow down to 1440 km/h to allow the opening of the main parachute. The glowing shock wave in front of the probe will reach temperatures of up to 12,000 Celsius. The probe is protected by a heat-shield, made from thermal tiles similar to those on the Space Shuttle. Huygens is a European project, part of NASA's Cassini spacecraft, and will arrive at Titan on 27 November 2004.