Cassini-Huygens

Cassini-Huygens revolutionized our understanding of Saturn's system, having launched in October 1997 and arrived at Saturn in July 2004 for a 13-year orbital tour. The mission discovered active geysers of water ice on Enceladus, revealing a subsurface ocean potentially capable of harboring life, and landed the Huygens probe on Titan in 2005 to uncover rivers of liquid methane. It outperforms even New Horizons in terms of sustained scientific output, returning over 450 gigabytes of data from 293 orbits and 163 targeted flybys. Its deliberate death dive into Saturn's atmosphere on September 15, 2017, protected those ocean worlds from contamination, a precaution that the International Space Station's end-of-life disposal plan lacks.