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Latitudinal variations of HCN, HC 3N, and C 2N 2 in Titan's stratosphere derived from Cassini CIRS data
Fletcher, L.; Irwin, P. G. J.; Teanby, N. A. +9 more
Mid- and far-infrared spectra from the Composite InfraRed Spectrometer (CIRS) have been used to determine volume mixing ratios of nitriles in Titan's atmosphere. HCN, HC 3N, C 2H 2, and temperature were derived from 2.5 cm -1 spectral resolution mid-IR mapping sequences taken during three flybys, which p…
Jupiter's atmospheric temperatures: From Voyager IRIS to Cassini CIRS
Achterberg, Richard K.; Flasar, F. Michael; Simon-Miller, Amy A. +4 more
Retrievals performed on Cassini Composite Infrared Spectrometer data obtained during the distant Jupiter flyby in 2000/2001 have been used to generate global temperature maps of the planet in the troposphere and stratosphere, but to higher latitudes than were shown previously by Flasar et al. [Flasar, F.M., 39 colleagues, 2004a. Nature 427, 132-13…
Interaction between eddies and mean flow in Jupiter's atmosphere: Analysis of Cassini imaging data
Ingersoll, Andrew P.; Del Genio, Anthony D.; Vasavada, Ashwin +2 more
Beebe et al. [Beebe, R.F., et al., 1980. Geophys. Res. Lett. 17, 1-4] and Ingersoll et al. [Ingersoll, A.P., et al., 1981. J. Geophys. Res. 86, 8733-8743] used images from Voyagers 1 and 2 to analyze the interaction between zonal winds and eddies in Jupiter's atmosphere. They reported a high positive correlation between Jupiter's eddy momentum flu…
Production, ionization and redistribution of O 2 in Saturn's ring atmosphere
Luhmann, J. G.; Tokar, R. L.; Johnson, R. E. +10 more
Molecular oxygen produced by the decomposition of icy surfaces is ubiquitous in Saturn's magnetosphere. A model is described for the toroidal O 2 atmosphere indicated by the detection of O2+ and O + over the main rings. The O 2 ring atmosphere is produced primarily by UV photon-induced decomposition of ice on the s…
The vertical structure of Titan's upper atmosphere from Cassini Ion Neutral Mass Spectrometer measurements
Waite, J. H.; Kasprzak, W. T.; Müller-Wodarg, I. +4 more
Data acquired by the Ion Neutral Mass Spectrometer (INMS) on the Cassini spacecraft during its close encounter with Titan on 26 October 2004 reveal the structure of its upper atmosphere. Altitude profiles of N 2, CH 4, and H 2, inferred from INMS measurements, determine the temperature, vertical mixing rate, and es…
A large cloud outburst at Titan's south pole
Brown, Michael E.; Bouchez, Antonin H.; Roe, Henry G. +1 more
Images of Titan acquired over five nights in October 2004 using the adaptive optics system at the Keck Observatory show dramatic increases in tropospheric cloud activity at the south pole compared with all other images of Titan clouds to date. During this time, Titan's south polar clouds brightened to more than 18 times their typical values. The C…
Reflectance spectra and chemical structure of Titan's tholins: Application to the analysis of Cassini Huygens observations
Quirico, E.; Schmitt, B.; Coll, P. +7 more
Titan's tholins are used as analogs of Titan's aerosols and N-rich organic solids present on many icy surfaces. However, it is not clear whether or not they are relevant analogs, and which kind of tholins should be used among a wide set available in literature. This paper presents reflectance spectral data of two tholins selected as end-members of…
Cassini RADAR observations of Enceladus, Tethys, Dione, Rhea, Iapetus, Hyperion, and Phoebe
Black, Gregory J.; Lorenz, Ralph D.; Hensley, Scott +17 more
Cassini 2.2-cm radar and radiometric observations of seven of Saturn's icy satellites yield properties that apparently are dominated by subsurface volume scattering and are similar to those of the icy Galilean satellites. Average radar albedos decrease in the order Enceladus/Tethys, Hyperion, Rhea, Dione, Iapetus, and Phoebe. This sequence most li…
Dissipation of Titan's south polar clouds
Brown, Michael E.; Trujillo, Chadwick A.; Bouchez, Antonin H. +2 more
Nearly all adaptive optics images of Titan taken between December 2001 and November 2004 showed tropospheric clouds located within 30° of the south pole. We report here on a dissipation of Titan's south polar clouds observed in twenty-nine Keck and Gemini images taken between December 2004 and April 2005. The near complete lack of south polar clou…
A global circulation model of Saturn's thermosphere
Yelle, R. V.; Müller-Wodarg, I. C. F.; Aylward, A. D. +1 more
We present the first 3-dimensional self-consistent calculations of the response of Saturn's global thermosphere to different sources of external heating, giving local time and latitudinal changes of temperatures, winds and composition at equinox and solstice. Our calculations confirm the well-known finding that solar EUV heating alone is insuffici…