Planetary Ring-Moon Systems: Observation and Interpretation

Grant #: NNX09AG14G
Senior Scientist: Mark Showalter

This study revisits the data from Voyager and other public-domain archives to better understand the latest problems in planetary ring science. We show that by careful processing and co-adding of many images, one can achieve hundred-fold improvements over what the eye can see; this makes it possible to address the following fundamental questions that are otherwise beyond our observational capabilities.   

(a) Search for the unseen parent bodies that produce the prevalent dust in the Uranian rings.   

(b) Investigate why some clumps in the Uranian mu ring have persisted for years, although they were expected to have sheared out in weeks.   

(c) Search for faint, outer rings of Neptune that might point to the presence of unseen moons.   

(d) Study the evolution of clumps in the F ring as they orbit, which provides important clues about how they form and evolve; ironically, Cassini has not obtained comparable data.   

(e) Search for resonant patterns in the rings of Uranus and Neptune, which could indicate the presence of unseen "shepherd" moons nearby.   

(f) Finally, apply numerical simulations and analytic models to explore the orbital variations of several Uranian moons, to estimate their masses and to understand their long-term dynamics. Although each problem is tied to a particular data set and a particular ring system, the phenomena to be studied have relevance to all ring-moons systems and, more broadly, to the dynamics of astrophysical disks. This work supports NASA's strategic goal to advance scientific knowledge of the origin and history of the Solar System, and the PGG program's goal to support analysis of data from planetary missions that are in public archives for investigations into the dynamical evolution of the planets, satellites, small Solar System bodies, and ring systems.