Rings Around Oddly Shaped Worlds

Can micron-sized dust survive in rings around small, irregular Solar System bodies? We explore this question for Chiron, Chariklo, Quaoar, and Haumea by modeling pebble-sized to sub-millimeter particles under solar radiation pressure, shadowing, heliocentric motion, and the rotating triaxial gravity of the host body. In spherical models, radiation pressure rapidly excites eccentricities and can drive small grains into the central body. Realistic triaxial shapes, however, change the picture: rapid apsidal precession suppresses this eccentricity growth and keeps dusty rings confined over 10^3 yr. For particles larger than roughly 7–40 micron, narrow rings remain dynamically stable. These results show that the oblate and elongated shapes of small bodies may be the key to preserving their surprisingly delicate dusty rings.