| Planetary rings provide a unique laboratory for the detailed study of complex self-gravitating systems. They also provide an analogy for the early stages of planet formation. My primary interest is in modeling ring particle interactions in the strong tidal field of a planet. Although the gravitational force exerted by metre-sized ring particles on each other is pretty small, there are nevertheless collective gravity effects that, when coupled with dissipative collisions, can lead to a variety of interesting ephemeral structures. |
In our simulations we concentrate on an orbiting patch of the ring (modeling an entire ring particle by particle is still beyond the capability of any computer). We have found that parts of Saturn's brightest rings, for example, the A and B rings, can form transient features such as gravitational wakes and loose aggregation. With our latest code we are capable of simulating hundreds of thousands of particles, giving unprecedented resolution for studying these phenomena. Using light-scattering code written by Carolyn Porco, we will be able to determine the unique lighting effects caused by wakes (such as the azimuthal brightness asymmetry) and relate them to past observations of Saturn's rings by Voyager and future observations by Cassini. Check back in the next few months for updates on our progress! Meanwhile, visit the Planetary Rings Node.
In this snapshot, the central patch is shown in green while shearing replicas are shown in magenta. Wake formation on a scale of about 100 m is easily seen in this simulation, which consisted of over 220,000 self-gravitating, colliding particles. This work was performed on the ARSC Cray T3E. HINT: Click on the image for the full animation, but beware -- it's big! (about 26 MB).
Follow Cassini's progress on its way to Saturn!
| Last modified: Jun 14, 2004 |
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