Cassini–Huygens

The Cassini–Huygens space-research mission, commonly called Cassini, involved a collaboration between NASA, the European Space Agency (ESA), and the Italian Space Agency (ASI) to send a probe to study the planet Saturn and its system, including its rings and natural satellites. The Flagship-class robotic spacecraft comprised both NASA's Cassini probe and ESA's Huygens lander, which landed on Saturn's largest moon, Titan.