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Ring Particle Composition and Size Distribution
Spilker, Linda; Clark, Roger; Filacchione, Gianrico +4 more
We review recent progress concerning the composition and size distribution of the particles in Saturn's main ring system, and describe how these properties vary from place to place. We discuss how the particle size distribution is measured, and how it varies radially. We note the discovery of unusually large "particles" in restricted radial bands.…
The Structure of Saturn's Rings
Nicholson, P. D.; French, R. G.; Murray, C. D. +3 more
Our understanding of the structure of Saturn's rings has evolved steadily since their discovery by Galileo Galilei in 1610. With each advance in observations of the rings over the last four centuries, new structure has been revealed, starting with the recognition that the rings are a disk by Huygens in 1656 through discoveries of the broad organiz…
Enceladus: An Active Cryovolcanic Satellite
Nimmo, Francis; Ingersoll, Andrew P.; Spencer, John R. +6 more
Enceladus is one of the most remarkable satellites in the solar system, as revealed by Cassini's detection of active plumes erupting from warm fractures near its south pole. This discovery makes Enceladus the only icy satellite known to exhibit ongoing internally driven geological activity. The activity is presumably powered by tidal heating maint…
Dynamics of Saturn's Dense Rings
Schmidt, Jürgen; Ohtsuki, Keiji; Rappaport, Nicole +2 more
The Cassini mission to Saturn opened a new era in the research of planetary rings, bringing data in unprecedented detail, monitoring the structure and properties of Saturn's ring system. The question of ring dynamics is to identify and understand underlying physical processes and to connect them to the observations in terms of mathematical models …
Icy Satellites of Saturn: Impact Cratering and Age Determination
Dones, Luke; McKinnon, William B.; Neukum, Gerhard +4 more
Saturn is the first giant planet to be visited by an orbiting spacecraft that can transmit large amounts of data to Earth. Crater counts on satellites from Phoebe inward to the regular satellites and ring moons are providing unprecedented insights into the origin and time histories of the impacting populations. Many Voyager-era scientists conclude…
Origin and Evolution of Saturn's Ring System
Dones, Luke; Hedman, Matthew M.; Esposito, Larry W. +2 more
The origin and long-term evolution of Saturn's rings is still an unsolved problem in modern planetary science. In this chapter we review the current state of our knowledge on this long-standing question for the main rings (A, Cassini Division, B, C), the F Ring, and the diffuse rings (E and G). During the Voyager era, models of evolutionary proces…
Saturn's Magnetospheric Configuration
Persoon, Ann M.; Gombosi, Tamas I.; Krupp, Norbert +5 more
This Chapter summarizes our current understanding of Saturn's magnetospheric configuration. Observations from the Cassini Prime and Equinox Missions have answered some questions and opened new ones. One of the fundamental questions of magnetospheric physics is what are the sources of the plasma that populate the magnetosphere. At Saturn, there is …
Saturn Atmospheric Structure and Dynamics
Baines, Kevin H.; Achterberg, Richard K.; Flasar, F. Michael +4 more
Saturn inhabits a dynamical regime of rapidly rotating, internally heated atmospheres similar to Jupiter. Zonal winds have remained fairly steady since the time of Voyager except in the equatorial zone and slightly stronger winds occur at deeper levels. Eddies supply energy to the jets at a rate somewhat less than on Jupiter and mix potential vort…
Clouds and Aerosols in Saturn's Atmosphere
Baines, K. H.; Sánchez-Lavega, A.; West, R. A. +1 more
In this chapter we review the photochemical and thermochemical equilibrium theories for the formation of condensate clouds and photochemical haze in Saturn's upper troposphere and stratosphere and show the relevant observations from ground-based and spacecraft instruments. Based on thermochemical equilibrium models we expect ammonia ice crystals t…
Saturn: Composition and Chemistry
Fouchet, Thierry; Moses, Julianne I.; Conrath, Barney J.
The chapter reviews our current knowledge of the molecular, elemental, and isotopic composition and atmospheric chemistry in Saturn 's shallow atmosphere, i.e., between the cloud levels and the homopause. We do not restrict the review to Cassini 's results, as past and current ground-based or Earth-based observations are still fundamental to draw …