Existence of moonlets in Saturn's rings inferred from the optical depth profile

Frank Spahn; Hanno Sponholz

doi:10.1038/339607a0

Voyager UVS observations of stellar occultations by the rings of Saturn

International Astronomical Union Colloquium ◽

10.1017/s0252921100101265 ◽

1984 ◽

Vol 75 ◽

pp. 265-277

Author(s):

J.B. Holbelg ◽

W.T. Forrester

Keyword(s):

Optical Depth ◽

Distance Scale ◽

Density Waves ◽

Ring Density ◽

Stellar Occultations ◽

Saturn’S Rings ◽

Saturn's Rings

ABSTRACTDuring the Voyager 1 and 2 Saturn encounters the ultraviolet spectrometers observed three separate stellar occultations by Saturn's rings. Together these three observations, which sampled the optical depth of the rings at resolutions from 3 to 6 km. can be used to establish a highly accurate distance scale allowing the identification of numerous ring features associated with resonances due to exterior satellites. Three separate observations of an eccentric ringlet near the location of the Titan apsidal resonance are discussed along with other ringlet-resonance associations occurring in the C ring. Density waves occurring in the A and B rings are reviewed and a detailed discussion of the analysis of one of these features is presented.

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Close-range remote sensing of Saturn’s rings during Cassini’s ring-grazing orbits and Grand Finale

Science ◽

10.1126/science.aau1017 ◽

2019 ◽

Vol 364 (6445) ◽

pp. eaau1017 ◽

Cited By ~ 5

Author(s):

Matthew S. Tiscareno ◽

Philip D. Nicholson ◽

Jeffrey N. Cuzzi ◽

Linda J. Spilker ◽

Carl D. Murray ◽

...

Keyword(s):

Remote Sensing ◽

Physical Properties ◽

Optical Depth ◽

Spectral Properties ◽

Dynamical Processes ◽

Ring Structures ◽

Close Range ◽

Saturn’S Rings ◽

F Ring ◽

Saturn's Rings

Saturn’s rings are an accessible exemplar of an astrophysical disk, tracing the Saturn system’s dynamical processes and history. We present close-range remote-sensing observations of the main rings from the Cassini spacecraft. We find detailed sculpting of the rings by embedded masses, and banded texture belts throughout the rings. Saturn-orbiting streams of material impact the F ring. There are fine-scaled correlations among optical depth, spectral properties, and temperature in the B ring, but anticorrelations within strong density waves in the A ring. There is no spectral distinction between plateaux and the rest of the C ring, whereas the region outward of the Keeler gap is spectrally distinct from nearby regions. These results likely indicate that radial stratification of particle physical properties, rather than compositional differences, is responsible for producing these ring structures.

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Saturn's Rings I Optical Depth Profiles from the 28 Sgr Occultation

Icarus ◽

10.1006/icar.2000.6356 ◽

2000 ◽

Vol 145 (2) ◽

pp. 474-501 ◽

Cited By ~ 33

Author(s):

P Nicholson

Keyword(s):

Optical Depth ◽

Depth Profiles ◽

Saturn’S Rings ◽

Saturn's Rings

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Saturn’s rings resolved by the VLA

International Astronomical Union Colloquium ◽

10.1017/s0252921100101010 ◽

1984 ◽

Vol 75 ◽

pp. 71-74

Author(s):

Imke de Pater ◽

John R. Dickel

Keyword(s):

High Resolution ◽

Optical Depth ◽

Ring Plane ◽

Radio Data ◽

Preliminary Results ◽

Saturn’S Rings ◽

Saturn's Rings

ABSTRACTHigh resolution radio data of Saturn have been obtained at 1.3, 2, 6 and 21 cm, at differentinclinationangles of the ring plane. Preliminary results on optical depth measurements in the rings are described.

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Dynamics of Gravitating Systems of Colliding Particles in Planetary Discs

Symposium - International Astronomical Union ◽

10.1017/s0074180900012730 ◽

1979 ◽

Vol 81 ◽

pp. 197-202 ◽

Cited By ~ 2

Author(s):

André Brahic

Keyword(s):

Solar System ◽

Optical Depth ◽

Interstellar Clouds ◽

Gravitational Perturbations ◽

Planets And Satellites ◽

Saturn’S Rings ◽

Gravitating Systems ◽

Saturn's Rings ◽

Solid Bodies ◽

The Universe

During this symposium on the dynamics of the solar system, we have mainly studied the movements of the bodies of the solar system submitted to gravitational perturbations. The next step is to take into account the physical collisions. Indeed, there can be little doubt that collisions between “macroscopic bodies” are of frequent occurence in the Universe. All kinds of quite different objects undergo such collisions: these may range from large interstellar clouds to small solid bodies in the solar system. Collisions have surely played an important role in the formation of planets and satellites and continue to play a central role in the behaviour of the planetary discs. For example for Saturn's rings, one can see intuitively that until the optical depth drops much below unity, the rings are still evolving. Each orbiting particle can be taken as occupying a kind of torus, and collisions will continue until there is only one particle in each such “orbital tube”; this corresponds to a very small optical depth.

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Comments on collision mechanics in ring systems

International Astronomical Union Colloquium ◽

10.1017/s0252921100101472 ◽

1984 ◽

Vol 75 ◽

pp. 407-422

Author(s):

William K. Hartmann

Keyword(s):

Asteroid Belt ◽

Surface Erosion ◽

Surface Layers ◽

Ring Systems ◽

Eclipse Observations ◽

Saturn’S Rings ◽

Saturn's Rings

ABSTRACTThe nature of collisions within ring systems is reviewed with emphasis on Saturn's rings. The particles may have coherent icy cores and less coherent granular or frosty surface layers, consistent with thermal eclipse observations. Present-day collisions of such ring particles do not cause catastrophic fragmentation of the particles, although some minor surface erosion and reaccretion is possible. Evolution by collisional fragmentation is thus not as important as in the asteroid belt.

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