Launched in 1997, Cassini survived a seven-year journey to Saturn. Once it arrived, it orbited the Saturnian system and sent back unprecedented images and data of Saturn, its rings, and its many moons.
Cassini deployed the Huygens probe to Saturn's moon Titan, and discovered liquid lakes on the surface. It sample geyser eruptions on the moon Enceladus, with tantalizing hints at the possibility of life. It tracked a 62,000-mile-long hurricane across Saturn's surface, took beautiful photos of the perfect hexagon at the north pole, and gave us important insights into the ringed world's turbulent interior. The plucky spacecraft also discovered six moons and showed how Saturn's natural satellites interact with its rings.
On September 15, 2017, Cassini ended its historic mission in spectacular fashion. To prevent any contamination of a moon with Earth bacteria -- which would interfere with our search for life -- the probe plunged into Saturn's clouds and burned up in the atmosphere.