The second ring-moon system of Uranus: discovery and dynamics.
Deep exposures of Uranus taken with the Hubble Space Telescope reveal two small moons and two faint rings. All of them orbit outside of Uranus's previously known (main) ring system but are interior to the large, classical moons. The outer new moon, U XXVI Mab, orbits at roughly twice the radius of the main rings and shares its orbit with a dust ring. The second moon, U XXVII Cupid, orbits just interior to the satellite Belinda. A second ring falls between the orbits of Portia and Rosalind, in a region with no known source bodies. Collectively, these constitute a densely packed, rapidly varying, and possibly unstable dynamical system.
Showalter
Mark R
MR
SETI Institute, 515 North Whisman Road, Mountain View, CA 94043, USA. mshowalter@seti.org
Lissauer
Jack J
JJ