The Cassini spacecraft swings in orbit around Saturn. Image: NASA.

The joint European-American mission Cassini-Huygens was launched 15 October 1997 onboard a Titan IV B/Centaur rocket from Cape Canaveral, Florida, USA, and after a seven-year flight arrived at its destination, Saturn. Cassini-Huygens travelled approximately 3.5 billion kilometres, performing two close fly-bys of Venus and one each of the Earth and Jupiter. Cassini-Huygens will investigate the giant gas planet Saturn and its system of moons.

Cassini-Huygens is a cooperative mission between the European, American and Italian space agencies (ESA, NASA, ASI). The mission consists of the Cassini orbiter and the descent probe Huygens. On 25 December 2004, Huygens separated from Cassini and on 14 January 2005 the probe entered the atmosphere of Saturn's moon Titan, landing on the surface after a three-hour descent.

There are a total of twelve scientific instruments onboard Cassini; a further six instruments are on Huygens. In Germany, several organisations are taking part in the mission, including the German Aerospace Center (DLR), institutes of the Max Planck Society (MPG) and several universities, as well as German space industry. These organisations have supplied several of the mission's instruments and/or components, or are working in specialised experimental areas. Germany's financial contribution to the mission amounts to approximately 115 million euros; the total cost of the mission amounted to approximately 3.3 billion dollars.