SMS scnews item created by Philip Treharne at Wed 21 Mar 2007 1219
Type: Seminar
Distribution: World
Expiry: 28 Mar 2007
Calendar1: 28 Mar 2007 1400-1500
CalLoc1: Eastern Avenue Lecture Theatre (Level 1)

Applied Maths Seminar: Latter -- Fine-scale structure in Saturn’s rings


Speaker: Dr Henrik Latter, University of Cambridge

Title: Fine-scale structure of Saturn’s rings

DATE: Wednesday, March 28
TIME: 2:00pm 
LOCATION: University of Sydney, Eastern Avenue Lecture Theatre (Level 1) 


The rings of Saturn are composed of trillions of icy boulders ranging in size from a few
centimetres to a few metres.  These particles undergo, on average, several very gentle
collisions per orbit.  In fact, their average impact velocity is barely 2 mm/s! But
these seemingly innocuous interactions, when allied with gravity, can have considerable
collective effects.  Over relatively short time-scales they sculpt the disk into
irregular radial patterns.  

This talk presents an introduction to the physics of planetary rings and concentrates on
the theory of fine-scale structure formation.  In particular, emphasis is placed on the
difficult modelling issues thrown up by a "gas" of infrequently colliding inelastic
particles.  We find that a planetary ring is in a unique regime which hydrodynamical
models cannot adequately capture.