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.

[1]  J. Lissauer,et al.  Orbital Stability of the Uranian Satellite System , 1997 .

[2]  J. Burns,et al.  Charged particle depletion surrounding Saturn's F ring - Evidence for a moonlet belt? , 1988 .

[3]  L. Esposito,et al.  G Ring Particle Sizes Derived from Ring Plane Crossing Observations , 1997 .

[4]  L. Esposito,et al.  A numerical model of the Uranian dust rings , 1990 .

[5]  F. Poulet,et al.  Saturn's Ring-Plane Crossings of August and November 1995: A Model for the New F-Ring Objects , 2000 .

[6]  L. Esposito,et al.  Moonlet Collisions and the Effects of Tidally Modified Accretion in Saturn's F Ring , 2002 .

[7]  R. H. Brown,et al.  Voyager 2 in the Uranian System: Imaging Science Results , 1986, Science.

[8]  M. Showalter,et al.  Seeing Ghosts: Photometry of Saturn's G Ring , 1993 .

[9]  S. Synnott,et al.  Orbits of the ten small satellites of Uranus , 1987 .

[10]  M. Showalter.  Detection of centimeter-sized meteoroid impact events in Saturn's F ring. , 1998, Science.

[11]  L. Esposito,et al.  Origins of the rings of Uranus and Neptune: 1. Statistics of satellite disruptions , 1992 .

[12]  E. Karkoschka.  Comprehensive Photometry of the Rings and 16 Satellites of Uranus with the Hubble Space Telescope , 2001 .

[13]  J. Lissauer,et al.  HST High-Resolution Backscatter Image of Saturn's G Ring , 2000 .

[14]  Voyager's Eleventh Discovery of a Satellite of Uranus and Photometry and the First Size Measurements of Nine Satellites , 2001 .

[15]  R. A. Jacobson,et al.  The Orbits of the Inner Uranian Satellites from Hubble Space Telescope and Voyager 2 Observations , 1998 .

[16]  J. Blamont,et al.  Ultraviolet Spectrometer Observations of Uranus , 1986, Science.