Vision and Voyages for Planetary Science in the - Solar System ...

FIGURE 8.11 After a comprehensive tour of the Jupiter system, the Jupiter Europa Orbiter (foreground)
is proposed to investigate Europa’s ice shell and ocean from Europa orbit, while the ESA Jupiter
Ganymede Orbiter (background) performs similar investigations at Ganymede. SOURCE: NASA/ESA.
Cassini Solstice Mission
Previously Recommended Missions
The Cassini spacecraft has been in Saturn orbit since 2004 and continues to deliver a steady
stream of remarkable discoveries. Recent satellite science highlights have included direct observations of
changing lake levels on Titan and high-resolution observations of the Enceladus plumes and their source
regions refining our understanding of plume composition and source conditions. The extension of the
mission through northern hemisphere summer solstice in 2017 will provide major opportunities for
satellite science. 60 Seasonal change is key to understanding the dynamics of Titan’s atmosphere and
interactions with the surface, and the mission extension will more than double our seasonal timebase,
including the critical period when the northern hemisphere lakes and polar vortex respond to major
increases in insolation as spring advances. Twelve additional Enceladus flybys will map its gravity field,
search for temporal and spatial changes in plume activity and composition, and provide unprecedented
detail on the south polar thermal emission and heat flow. In addition, flybys of Rhea and Dione will
probe their interiors and search for endogenic activity.
PREPUBLICATION COPY—SUBJECT TO FURTHER EDITORIAL CORRECTION
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