Towards a theory for the uranian rings

  title={Towards a theory for the uranian rings},
  author={Peter Goldreich and Scott Tremaine},
Interparticle collisions, radiation drag and differential precession all tend to disrupt the rings of Uranus. The first two effects lead to radial spreading which would disrupt a free ring in ≲108 yr. We propose that the rings are confined in radius by gravitational torques from a series of small satellites that orbit within the ring system. Differential precession tends to destroy the apse alignment of the elliptical ε ring. We suggest that apse alignment is maintained by the self-gravity of… 
Inclinations of the uranian rings
Rings formed with the birth of a planet are thought to arise after planetary condensation, from material remaining within the outer accretion limit—which has a radius of approximately two planetary
Three-dimensional Dynamics of Narrow Planetary Rings
Narrow planetary rings are eccentric and inclined. Particles within a given ring must therefore share the same pericenter and node. We solve for the three-dimensional geometries and mass
On the formation and stability of Uranus' rings
We discuss the possibility of outlining a ‘global’ model of formation and evolution for the Uranian rings with the minimum allowance for arbitrary assumptions. A condition for the stability of the
On the shepherding of Uranian epsilon ring
To explain the long-term existence of Uranian narrow rings, we study the dynamical evolution of Uranian epsilon ring under the influence of its two shepherding satellites: Cordelia and Ophelia. The
The Torque at a Lindblad Vertical Resonance
A fairly uniform, rapidly and differentially rotating disk of rarely colliding particles (when the frequency of interparticle collisions is much smaller than the local orbital frequency) in a
Phase-Space Structure for Narrow Planetary Rings
We address the occurrence of narrow planetary rings under the interaction with shepherds. Our approach is based on a Hamiltonian framework of non–interacting particles where open motion (escape)
An Inelastic Collision Model for the Evolution of “Planetary Rings”
We show that ringlets of a planet can be formed by inelastic collisions. If the collision law is v ′ =- e v ( v ′ and v are relative velocities after and before the collision), then the configuration
A note on the horseshoe confinement model: The Poynting-Robertson effect
In the present work we numerically simulated the motion of particles coorbital to a small satellite under the Poynting-Robertson light drag effect in order to verify the symmetry suggested by Dermott
Simulating the Smallest Ring World of Chariklo
A ring system consisting of two dense narrow rings has been discovered around Centaur Chariklo. The existence of these rings around a small object poses various questions about their origin,


The rings of Uranus: results of the 10 April 1978 occultation.
Observations of the 10 April 1978 stellar occultation by the rings of Uranus are presented. Nine rings were observed and their radii and widths are calculated. Rings η,y, and δ are found to be most
The rings of Uranus: theory
The structure of the recently discovered rings of Uranus is accounted for by a series of orbital resonances with the satellites Ariel, Titania and Oberon. The observations and their interpretation
Quantitative analysis of the Dermott–Gold theory for Uranus's rings
DERMOTT and Gold1 have attempted to explain the locations of Uranus's rings in terms of resonances between ring particles and pairs of satellites, such that each particle librates about consecutive
The occultation of BD -15 deg 3969 by the rings of Uranus
Photoelectric observations of the December 23, 1977, occultation of BD -15 deg 3969 by the rings of Uranus are analyzed. The observations were made with a 1.5-m IR flux collector and clearly show the
The rings of Uranus
AT least five rings encircle the planet Uranus—as indicated by five brief occultations of the star SAO 158687 that occurred both before and after its occultation by Uranus on 10 March 1977. We
The radii of Uranian rings alpha, beta, gamma, delta, epsilon, eta, 4, 5, and 6 from their occultations of SAO 158687
All available timing data for the occultations of SAO 158687 on March 10, 1977, by the cited rings of Uranus are analyzed. Least-squares fits to the data are performed using a model which postulates
Revenge of tiny Miranda
DERMOTT and Gold1 have proposed a resonance model for the rings of Uranus. They assume the rings are, in fact, arcs composed of small particles librating about stable resonances determined by pairs