For thirteen years, from 2004 to 2017, the Cassini-Huygens mission conducted a detailed survey of the Saturn system, fundamentally altering our understanding of gas giants and their satellites.
Titan, Saturn's largest moon, was a major surprise, with a diameter of 3,200 miles, almost 50% bigger than Earth's moon. Despite its size, Titan appears as a barely visible whitish speck above Saturn's rings.
The planet's ring system, once thought to be relatively placid, was shown to be remarkably dynamic, composed of over 99% water ice, with particles ranging in size from micrometers to tens of meters.
Author's summary: Cassini revealed Titan's unique features.