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Publications

Filter Total Items: 335

Distribution of icy particles across Enceladus' surface as derived from Cassini-VIMS measurements

The surface of Enceladus consists almost completely of water ice. As the band depths of water ice absorptions are sensitive to the size of particles, absorptions can be used to map variations of icy particles across the surface. The Visual and Infrared Mapping Spectrometer (VIMS) observed Enceladus with a high spatial resolution during three Cassini flybys in 2005 (orbits EN 003, EN 004 and EN 011
Authors
R. Jaumann, K. Stephan, G. B. Hansen, R. N. Clark, B. J. Buratti, R. H. Brown, K. H. Baines, S.F. Newman, G. Bellucci, G. Filacchione, A. Coradini, D. P. Cruikshank, C.A. Griffith, C. A. Hibbitts, T. B. McCord, R.M. Nelson, P. D. Nicholson, Christophe Sotin, R. Wagner

Identification of spectral units on Phoebe

We apply a multivariate statistical method to the Phoebe spectra collected by the VIMS experiment onboard the Cassini spacecraft during the flyby of June 2004. The G-mode clustering method, which permits identification of the most important features in a spectrum, is used on a small subset of data, characterized by medium and high spatial resolution, to perform a raw spectral classification of the
Authors
A. Coradini, F. Tosi, A.I. Gavrishin, F. Capaccioni, P. Cerroni, G. Filacchione, A. Adriani, R. H. Brown, G. Bellucci, V. Formisano, E. D'Aversa, J. I. Lunine, K. H. Baines, J.-P. Bibring, B. J. Buratti, R. N. Clark, D. P. Cruikshank, M. Combes, P. Drossart, R. Jaumann, Y. Langevin, D. L. Matson, T. B. McCord, V. Mennella, R.M. Nelson, P. D. Nicholson, B. Sicardy, Christophe Sotin, M.M. Hedman, G. B. Hansen, C. A. Hibbitts, M. Showalter, C. Griffith, G. Strazzulla

Infrared (0.83–5.1 μm) photometry of Phoebe from the Cassini Visual Infrared Mapping Spectrometer

Three weeks prior to the commencement of Cassini's   4 year tour of the saturnian system, the spacecraft executed a close flyby of the outer satellite Phoebe. The infrared channel of the Visual Infrared Mapping Spectrometer (VIMS) obtained images of reflected light over the 0.83–5.1 μm spectral range with an average spectral resolution of 16.5 nm, spatial resolution up to 2 km, and over a range of
Authors
B. J. Buratti, K. Soderlund, J. Bauer, J. A. Mosher, M.D. Hicks, D.P. Simonelli, R. Jaumann, R. N. Clark, R. H. Brown, D. P. Cruikshank, T. Momary

Phyllosilicate and sulfate-hematite deposits within Miyamoto crater in Southern Sinus Meridiani, Mars

Orbital topographic, image, and spectral data show that sulfate- and hematite-bearing plains deposits similar to those explored by the MER rover Opportunity unconformably overlie the northeastern portion of the 160 km in diameter Miyamoto crater. Crater floor materials exhumed to the west of the contact exhibit CRISM and OMEGA NIR spectral signatures consistent with the presence of Fe/Mg-rich smec
Authors
S.M. Wiseman, R. E. Arvidson, J. C. Andrews-Hanna, R. N. Clark, N.L. Lanza, D. des Marais, G.A. Marzo, R.V. Morris, S.L. Murchie, Horton E. Newsom, E.Z. Noe Dobrea, A.M. Ollila, F. Poulet, T. L. Roush, F.P. Seelos, G.A. Swayze

Complex structure within Saturn's infrared aurora

The majority of planetary aurorae are produced by electrical currents flowing between the ionosphere and the magnetosphere which accelerate energetic charged particles that hit the upper atmosphere. At Saturn, these processes collisionally excite hydrogen, causing ultraviolet emission, and ionize the hydrogen, leading to H3+ infrared emission. Although the morphology of these aurorae is affected b
Authors
T. Stallard, S. Miller, M. Lystrup, N. Achilleos, E.J. Bunce, C.S. Arridge, M.K. Dougherty, S.W.H. Cowley, S.V. Badman, D.L. Talboys, R. H. Brown, K. H. Baines, B. J. Buratti, R. N. Clark, Christophe Sotin, P. D. Nicholson, P. Drossart

Compositional mapping of Saturn's satellite Dione with Cassini VIMS and implications of dark material in the Saturn system

Cassini VIMS has obtained spatially resolved imaging spectroscopy data on numerous satellites of Saturn. A very close fly-by of Dione provided key information for solving the riddle of the origin of the dark material in the Saturn system. The Dione VIMS data show a pattern of bombardment of fine, sub-0.5-??m diameter particles impacting the satellite from the trailing side direction. Multiple line
Authors
R. N. Clark, J. M. Curchin, R. Jaumann, D. P. Cruikshank, R. H. Brown, T.M. Hoefen, K. Stephan, Johnnie N. Moore, B. J. Buratti, K. H. Baines, P. D. Nicholson, R.M. Nelson

Orbital identification of carbonate-bearing rocks on Mars

Geochemical models for Mars predict carbonate formation during aqueous alteration. Carbonate-bearing rocks had not previously been detected on Mars' surface, but Mars Reconnaissance Orbiter mapping reveals a regional rock layer with near-infrared spectral characteristics that are consistent with the presence of magnesium carbonate in the Nili Fossae region. The carbonate is closely associated with
Authors
B.L. Ehlmann, J.F. Mustard, S.L. Murchie, F. Poulet, J.L. Bishop, A.J. Brown, W. M. Calvin, R. N. Clark, D.J. Des Marais, R.E. Milliken, L.H. Roach, T. L. Roush, G.A. Swayze, J.J. Wray

Fluvial erosion and post-erosional processes on Titan

The surface of Titan has been revealed by Cassini observations in the infrared and radar wavelength ranges as well as locally by the Huygens lander instruments. Sand seas, recently discovered lakes, distinct landscapes and dendritic erosion patterns indicate dynamic surface processes. This study focus on erosional and depositional features that can be used to constrain the amount of liquids involv
Authors
R. Jaumann, R. H. Brown, K. Stephan, J. W. Barnes, L. A. Soderblom, Christophe Sotin, S. Le Mouelic, R. N. Clark, J. Soderblom, B. J. Buratti, R. Wagner, T. B. McCord, S. Rodriguez, K. H. Baines, D. P. Cruikshank, P. D. Nicholson, C.A. Griffith, M. Langhans, R. D. Lorenz

Mapping and interpretation of Sinlap crater on Titan using Cassini VIMS and RADAR data

Only a few impact craters have been unambiguously detected on Titan by the Cassini-Huygens mission. Among these, Sinlap is the only one that has been observed both by the RADAR and VIMS instruments. This paper describes observations at centimeter and infrared wavelengths which provide complementary information about the composition, topography, and surface roughness. Several units appear in VIMS f
Authors
S. Le Mouelic, P. Paillou, M.A. Janssen, J. W. Barnes, S. Rodriguez, Christophe Sotin, R. H. Brown, K. H. Baines, B. J. Buratti, R. N. Clark, M. Crapeau, P.J. Encrenaz, R. Jaumann, D. Geudtner, F. Paganelli, L. Soderblom, G. Tobie, S. Wall

Phyllosilicate diversity and past aqueous activity revealed at Mawrth Vallis, Mars

Observations by the Mars Reconnaissance Orbiter/Compact Reconnaissance Imaging Spectrometer for Mars in the Mawrth Vallis region show several phyllosilicate species, indicating a wide range of past aqueous activity. Iron/magnesium (Fe/Mg)-smectite is observed in light-toned outcrops that probably formed via aqueous alteration of basalt of the ancient cratered terrain. This unit is overlain by rock
Authors
J.L. Bishop, E.Z.N. Dobrea, N.K. McKeown, M. Parente, B.L. Ehlmann, J.R. Michalski, R.E. Milliken, F. Poulet, G.A. Swayze, J.F. Mustard, S.L. Murchie, J.-P. Bibring

Hydrated silicate minerals on Mars observed by the Mars Reconnaissance Orbiter CRISM instrument

Phyllosilicates, a class of hydrous mineral first definitively identified on Mars by the OMEGA (Observatoire pour la Mineralogie, L’Eau, les Glaces et l’Activitié) instrument1,2, preserve a record of the interaction of water with rocks on Mars. Global mapping showed that phyllosilicates are widespread but are apparently restricted to ancient terrains and a relatively narrow range of mineralogy (Fe
Authors
J.F. Mustard, S.L. Murchie, S.M. Pelkey, B.L. Ehlmann, R.E. Milliken, J. A. Grant, J.-P. Bibring, F. Poulet, J. Bishop, E. N. Dobrea, L. Roach, F. Seelos, R. E. Arvidson, S. Wiseman, R. Green, C. Hash, D. Humm, E. Malaret, J.A. McGovern, K. Seelos, T. Clancy, R. Clark, D. des Marais, N. Izenberg, A. Knudson, Y. Langevin, T. Martin, P. McGuire, Robert Morris, M. Robinson, T. Roush, M. Smith, G. Swayze, H. Taylor, T. Titus, M. Wolff

The identification of liquid ethane in Titan's Ontario Lacus

Titan was once thought to have global oceans of light hydrocarbons on its surface, but after 40 close flybys of Titan by the Cassini spacecraft, it has become clear that no such oceans exist. There are, however, features similar to terrestrial lakes and seas, and widespread evidence for fluvial erosion, presumably driven by precipitation of liquid methane from Titan's dense, nitrogen-dominated atm
Authors
R. H. Brown, L. A. Soderblom, J.M. Soderblom, R. N. Clark, R. Jaumann, J. W. Barnes, Christophe Sotin, B. Buratti, K. H. Baines, P. D. Nicholson