Cassini/Huygens spacecraft. Artwork of the Cassini spacecraft releasing the Huygens probe (bottom right) over Titan, one of the moons of the ringed planet Saturn. The dish-shaped Huygens probe will enter the atmosphere of Titan at a speed of about 22,000 kilometres per hour. Using parachutes to slow itself down, Huygens will carry instruments down to Titan's surface and broadcast data for up to 30 minutes. Cassini will orbit Saturn for four years, and will study the planet, its rings, and its moons. Cassini was launched in October 1997 and is expected to reach Saturn in July 2004. The Huygens probe will enter Titan's atmosphere in November 2004.