The Cassini spacecraft, launched in October 1997, entered a Saturn-centered orbit in July 2004. It is instrumented for a wide range of remote sensing and in situ observations. It delivered the ESA-built Huygens Probe to investigate Titan.

The Cassini mission to Saturn is one of the most ambitious efforts in planetary space exploration ever mounted.
A joint endeavor of NASA, the European Space Agency (ESA) and the Italian space agency, Agenzia Spaziale Italiana (ASI),
Cassini is a sophisticated robotic spacecraft orbiting the ringed planet and studying the Saturnian system in detail.
Cassini also carried a probe called Huygens, which parachuted to the surface of Saturn’s largest moon, Titan, in January 2005 and
returned spectacular results.

Cassini completed its initial four-year mission to explore the Saturn System in June 2008,
a first extension (the Cassini Equinox Mission) in September 2010, and a second extension
(the Cassini Solstice Mission) in late 2016.

From that date until September 2017, the Cassini spacecraft has begun a daring set of orbits (the Cassini Grand Finale) where the spacecraft
repeatedly has climbed high above Saturn’s poles, flying just outside its narrow F ring 20 times.
After a last targeted Titan flyby, the spacecraft has then dived between Saturn’s uppermost atmosphere and its innermost ring 22 times.
As Cassini has plunged past Saturn, the spacecraft has collected rich and valuable information far beyond the mission’s original plan,
including measuring Saturn’s gravitational and magnetic fields, determining ring mass, sampling the atmosphere and ionosphere,
and making the last views of Enceladus.