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Titan's methane cycle
Atreya, Sushil K.; Ferri, Francesca; Niemann, Hasso B. +5 more
Methane is key to sustaining Titan's thick nitrogen atmosphere. However, methane is destroyed and converted to heavier hydrocarbons irreversibly on a relatively short timescale of approximately 10-100 million years. Without the warming provided by CH 4-generated hydrocarbon hazes in the stratosphere and the pressure induced opacity in t…
Cassini observations of Saturn's inner plasmasphere: Saturn orbit insertion results
Coates, A. J.; Johnson, R. E.; Thomsen, M. +13 more
We present new and definitive results of Cassini plasma spectrometer (CAPS) data acquired during passage through Saturn's inner plasmasphere by the Cassini spacecraft during the approach phase of the Saturn orbit insertion period. This analysis extends the original analysis of Sittler et al. [2005. Preliminary results on Saturn's inner plasmaspher…
Cassini RPWS observations of dust in Saturn's E Ring
Gurnett, D. A.; Kurth, W. S.; Averkamp, T. F. +1 more
The Cassini radio and plasma wave science (RPWS) instrument is sensitive to few-micron dust grains impacting on the spacecraft at relative speeds of order 10 km/s. Through the first year or so of operations in orbit at Saturn, the RPWS has made a number of both inclined and equatorial crossings of the E ring, particularly near the orbit of Encelad…
Composition of Titan's surface from Cassini VIMS
Sotin, C.; Brown, R. H.; Buratti, B. J. +15 more
Titan's bulk density along with Solar System formation models indicates considerable water as well as silicates as its major constituents. This satellite's dense atmosphere of nitrogen with methane is unique. Deposits or even oceans of organic compounds have been suggested to exist on Titan's solid surface due to UV-induced photochemistry in the a…
Cassini/VIMS hyperspectral observations of the HUYGENS landing site on Titan
Le Mouélic, S.; Rodriguez, S.; Sotin, C. +8 more
Titan is one of the primary scientific objectives of the NASA-ESA-ASI Cassini-Huygens mission. Scattering by haze particles in Titan's atmosphere and numerous methane absorptions dramatically veil Titan's surface in the visible range, though it can be studied more easily in some narrow infrared windows. The Visual and Infrared Mapping Spectrometer…
The electrostatic potential of E ring particles
Beckmann, U.; Kempf, S.; Srama, R. +3 more
Saturn's E ring is remarkable not only for its huge size. Based on optical measurements the ring was surprisingly found to mainly consist of ice particles of uniform size (radii between 0.3 and 2 microns) [Nicholson et al., 1996. Observations of Saturn's ring-plane crossing in August and November. Science 272, 509-516], though the source of the ri…
Initial interpretation of Titan plasma interaction as observed by the Cassini plasma spectrometer: Comparisons with Voyager 1
Coates, A. J.; Crary, F.; Johnson, R. E. +15 more
The Cassini plasma spectrometer (CAPS) instrument made measurements of Titan's plasma environment when the Cassini Orbiter flew through the moon's plasma wake October 26, 2004 (flyby TA). Initial CAPS ion and electron measurements from this encounter will be compared with measurements made by the Voyager 1 plasma science instrument (PLS). The comp…
E ring dust sources: Implications from Cassini's dust measurements
Schmidt, Jürgen; Albers, Nicole; Spahn, Frank +6 more
The Enceladus flybys of the Cassini spacecraft are changing our understanding of the origin and sustainment of Saturn's E ring. Surprisingly, beyond the widely accepted dust production caused by micrometeoroid impacts onto the atmosphereless satellites (the impactor-ejecta process), geophysical activities have been detected at the south pole of En…
Titan's surface albedo variations over a Titan season from near-infrared CFHT/FTS spectra
Lellouch, E.; Rannou, P.; Coustenis, A. +5 more
We have observed Titan in a series of campaigns from 1991 to 1996 with the Fourier Transform Spectrometer on the CFH telescope. The data acquired provide a lightcurve from the geometric albedos in the 0.9- 2.5µm spectral region. The 1991-1993 data were previously analyzed in Coustenis et al. [1995. Titan's surface: composition and variabilit…
In situ dust measurements in the inner Saturnian system
Grande, M.; Beckmann, U.; Kempf, S. +38 more
In July 2004 the Cassini-Huygens mission reached the Saturnian system and started its orbital tour. A total of 75 orbits will be carried out during the primary mission until August 2008. In these four years Cassini crosses the ring plane 150 times and spends approx. 400 h within Titan's orbit. The Cosmic Dust Analyser (CDA) onboard Cassini charact…