The mission extension builds upon the success of the primary mission. Some key scientific objectives of this extended mission are :
- to study in more detail the Saturnian moons, in particular Titan and Enceladus;
- to monitor seasonal effects on Titan and Saturn;
- to explore new regions of the Saturnian magnetosphere;
- to observe the unique ring geometry of the Saturn equinox in August 2009 - when sunlight will pass directly through the plane of the rings.
Source : ESA Science Cassini-Huygens homepage