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Enceladus: An Active Ice World in the Saturn System
Nimmo, Francis; Spencer, John R.
Enceladus, one of the mid-sized icy moons of Saturn, has an importance to planetary science far greater than its modest 504-km diameter would suggest. Intensive exploration of Enceladus by the Cassini Saturn orbiter has revealed that it is the only known icy world in the solar system with ongoing deep-seated geological activity. Active tectonic fr…
Titan's Methane Weather
Roe, Henry G.
Conditions in Titan's troposphere are near the triple point of methane, the second most abundant component of its atmosphere. Our understanding of Titan's lower atmosphere has shifted considerably in the past decade. Ground-based observations, Hubble Space Telescope images, and data returned from the Cassini and Huygens spacecraft show that Titan'…
Composition, Structure, Dynamics, and Evolution of Saturn's Rings
Esposito, Larry W.
Cassini observations confirm that Saturn's rings are predominantly water ice. The particles in Saturn's rings cover a range of sizes, from dust to small moons. Occultation results show the particles form temporary elongated aggregates tens of meters across. Some of the ring structure is created by moons, others by various instabilities. Data from …
Rivers, Lakes, Dunes, and Rain: Crustal Processes in Titan's Methane Cycle
Lorenz, Ralph D.; Lunine, Jonathan I.
Titan exhibits ample surface and crustal processes including lakes and seas, fluvial erosive features, possibly subsurface reservoirs of liquid, and rainfall. Together these constitute strong evidence for a multicomposition hydrological system, composed mostly of methane and ethane as well as trace amounts of other alkanes. Estimates of the volume…
Hubble Space Telescope Observations of Planets and Satellites
James, Philip B.; Lee, Steven W.
Although exploration by remote, in situ spacecraft has been the primary tool used in scientific exploration of the planets and other solar system objects for the last three decades, the unique capabilities of the Hubble Space Telescope (HST) have made it an invaluable tool for solar system research and have led to many important discoveries. HST's…