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Evidence for montmorillonite or its compositional equivalent in Columbia Hills, Mars Evidence for montmorillonite or its compositional equivalent in Columbia Hills, Mars

During its exploration of the Columbia Hills, the Mars Exploration Rover "Spirit" encountered several similar samples that are distinctly different from Martian meteorites and known Gusev crater soils, rocks, and sediments. Occurring in a variety of contexts and locations, these "Independence class" samples are rough-textured, iron-poor (equivalent FeO ??? 4 wt%), have high Al/Si ratios...
Authors
B. C. Clark, R. E. Arvidson, Ralf Gellert, R.V. Morris, D. W. Ming, L. Richter, S. W. Ruff, J.R. Michalski, W. H. Farrand, A. S. Yen, Kenneth E. Herkenhoff, R. Li, S. W. Squyres, C. Schroder, G. Klingelhofer, J.F. Bell

Athabasca Valles, Mars: A lava-draped channel system Athabasca Valles, Mars: A lava-draped channel system

Athabasca Valles is a young outflow channel system on Mars that may have been carved by catastrophic water floods. However, images acquired by the High-Resolution Imaging Science Experiment camera onboard the Mars Reconnaissance Orbiter spacecraft reveal that Athabasca Valles is now entirely draped by a thin layer of solidified lava - the remnant of a once-swollen river of molten rock...
Authors
Windy L. Jaeger, Laszlo P. Keszthelyi, Alfred S. McEwen, Colin M. Dundas, Paul C. Russell

Evaluating planetary digital terrain models-The HRSC DTM test Evaluating planetary digital terrain models-The HRSC DTM test

The High Resolution Stereo Camera (HRSC) has been orbiting the planet Mars since January 2004 onboard the European Space Agency (ESA) Mars Express mission and delivers imagery which is being used for topographic mapping of the planet. The HRSC team has conducted a systematic inter-comparison of different alternatives for the production of high resolution digital terrain models (DTMs)...
Authors
C. Heipke, J. Oberst, J. Albertz, M. Attwenger, P. Dorninger, E. Dorrer, M. Ewe, S. Gehrke, K. Gwinner, H. Hirschmuller, J.R. Kim, Randolph L. Kirk, H. Mayer, Jan-Peter Muller, R. Rengarajan, M. Rentsch, R. Schmidt, F. Scholten, J. Shan, M. Spiegel, M. Wahlisch, G. Neukum

Windy Mars: A dynamic planet as seen by the HiRISE camera Windy Mars: A dynamic planet as seen by the HiRISE camera

With a dynamic atmosphere and a large supply of particulate material, the surface of Mars is heavily influenced by wind-driven, or aeolian, processes. The High Resolution Imaging Science Experiment (HiRISE) camera on the Mars Reconnaissance Orbiter (MRO) provides a new view of Martian geology, with the ability to see decimeter-size features. Current sand movement, and evidence for recent...
Authors
Nathan T. Bridges, Paul E. Geissler, Alfred S. McEwen, B.J. Thomson, Frank C. Chuang, Kenneth E. Herkenhoff, Laszlo P. Keszthelyi, Sara Martinez-Alonso

Meter-scale morphology of the north polar region of mars Meter-scale morphology of the north polar region of mars

Mars' north pole is covered by a dome of layered ice deposits. Detailed (∼30 centimeters per pixel) images of this region were obtained with the High-Resolution Imaging Science Experiment on board the Mars Reconnaissance Orbiter (MRO). Planum Boreum basal unit scarps reveal cross-bedding and show evidence for recent mass wasting, flow, and debris accumulation. The north polar layers...
Authors
Kenneth E. Herkenhoff, S. Byrne, P.S. Russell, K.E. Fishbaugh, A. S. McEwen

Mars reconnaissance orbiter's high resolution imaging science experiment (HiRISE) Mars reconnaissance orbiter's high resolution imaging science experiment (HiRISE)

The HiRISE camera features a 0.5 m diameter primary mirror, 12 m effective focal length, and a focal plane system that can acquire images containing up to 28 Gb (gigabits) of data in as little as 6 seconds. HiRISE will provide detailed images (0.25 to 1.3 m/pixel) covering ∼1% of the Martian surface during the 2‐year Primary Science Phase (PSP) beginning November 2006. Most images will...
Authors
Alfred S. McEwen, Eric M. Eliason, James W. Bergstrom, Nathan T. Bridges, Candice J. Hansen, W. Alan Delamere, John A. Grant, Virginia C. Gulick, Kenneth E. Herkenhoff, Laszlo P. Keszthelyi, Randolph L. Kirk, Michael T. Mellon, Steven W. Squyres, Nicolas Thomas, Catherine M. Weitz

Titan's surface from Cassini RADAR SAR and high resolution radiometry data of the first five flybys Titan's surface from Cassini RADAR SAR and high resolution radiometry data of the first five flybys

The first five Titan flybys with Cassini's Synthetic Aperture RADAR (SAR) and radiometer are examined with emphasis on the calibration and interpretation of the high-resolution radiometry data acquired during the SAR mode (SAR-radiometry). Maps of the 2-cm wavelength brightness temperature are obtained coincident with the SAR swath imaging, with spatial resolution approaching 6 km. A...
Authors
F. Paganelli, Michael A. Janssen, B. Stiles, R. West, Ralf D. Lorenz, Jonathan I. Lunine, Stephen D. Wall, Philip S. Callahan, Rosaly Lopes, Ellen R. Stofan, Randolph L. Kirk, W.T.K. Johnson, L. Roth, Charles Elachi

New estimates for Io eruption temperatures: Implications for the interior New estimates for Io eruption temperatures: Implications for the interior

The initial interpretation of Galileo data from Jupiter's moon, Io, suggested eruption temperatures ≥1600°C. Tidal heating models have difficulties explaining Io's prodigious heat flow if the mantle is >1300°C, although we suggest that temperatures up to ~1450°C may be possible. In general, Io eruption temperatures have been overestimated because the incorrect thermal model has been...
Authors
Laszlo P. Keszthelyi, Windy L. Jaeger, Moses P. Milazzo, Jani Radebaugh, Ashley G. Davies, Karl L. Mitchell

Cryovolcanic features on Titan's surface as revealed by the Cassini Titan Radar Mapper Cryovolcanic features on Titan's surface as revealed by the Cassini Titan Radar Mapper

The Cassini Titan Radar Mapper obtained Synthetic Aperture Radar images of Titan's surface during four fly-bys during the mission's first year. These images show that Titan's surface is very complex geologically, showing evidence of major planetary geologic processes, including cryovolcanism. This paper discusses the variety of cryovolcanic features identified from SAR images, their...
Authors
Rosaly Lopes, K. L. Mitchell, Ellen R. Stofan, Jonathan I. Lunine, Ralf D. Lorenz, F. Paganelli, Randolph L. Kirk, C. A. Wood, Stephen D. Wall, L.E. Robshaw, A.D. Fortes, Catherine D. Neish, Jani Radebaugh, E. Reffet, S.J. Ostro, Charles Elachi, M.D. Allison, Y. Anderson, R. Boehmer, G. Boubin, Philip S. Callahan, P. Encrenaz, E. Flamini, G. Francescetti, Y. Gim, G. Hamilton, S. Hensley, Michael A. Janssen, W.T.K. Johnson, K. Kelleher, D.O. Muhleman, G. Ori, R. Orosei, G. Picardi, F. Posa, L.E. Roth, R. Seu, S. Shaffer, Laurence A. Soderblom, B. Stiles, S. Vetrella, R.D. West, L. Wye, H. A. Zebker

Initial insights from 2.5D hydraulic modeling of floods in Athabasca Valles, Mars Initial insights from 2.5D hydraulic modeling of floods in Athabasca Valles, Mars

We present the first application of a 2.5D hydraulic model to catastrophic floods on Mars. This model simulates flow over complex topography and incorporates flood dynamics that could not be modeled in the earlier 1D models. We apply this model to Athabasca Valles, the youngest outflow channel on Mars, investigating previous bank-full discharge estimates and utilizing the interpolated...
Authors
Laszlo P. Keszthelyi, Roger P. Denlinger, D. R. H. O’Connell, Devon M. Burr

Near-infrared spectral mapping of Titan's mountains and channels Near-infrared spectral mapping of Titan's mountains and channels

We investigate the spectral reflectance properties of channels and mountain ranges on Titan using data from Cassini's Visual and Infrared Mapping Spectrometer (VIMS) obtained during the T9 encounter (26 December 2005). We identify the location of channels and mountains using synthetic aperture radar maps obtained from Cassini's RADAR instrument during the T13 (30 April 2006) flyby...
Authors
Jason W. Barnes, Jani Radebaugh, Robert H. Brown, Steve Wall, Laurence A. Soderblom, Jonathan I. Lunine, Devon M. Burr, Christophe Sotin, Stephane Le Mouelic, Sebastien Rodriguez, Bonnie J. Buratti, Roger N. Clark, Kevin H. Baines, Ralf Jaumann, Philip D. Nicholson, Randolph L. Kirk, Rosaly Lopes, Ralph D. Lorenz, Ken Mitchell, Charles A. Wood

Correlations between Cassini VIMS spectra and RADAR SAR images: Implications for Titan's surface composition and the character of the Huygens Probe Landing Site Correlations between Cassini VIMS spectra and RADAR SAR images: Implications for Titan's surface composition and the character of the Huygens Probe Landing Site

Titan's vast equatorial fields of RADAR-dark longitudinal dunes seen in Cassini RADAR synthetic aperture images correlate with one of two dark surface units discriminated as “brown” and “blue” in Visible and Infrared Mapping Spectrometer (VIMS) color composites of short-wavelength infrared spectral cubes (RGB as 2.0, 1.6, 1.3 μm). In such composites bluer materials exhibit higher...
Authors
Laurence A. Soderblom, Randolph L. Kirk, Jonathan I. Lunine, Jeffrey A. Anderson, Kevin H. Baines, Jason W. Barnes, Janet M. Barrett, Robert H. Brown, Bonnie J. Buratti, Roger N. Clark, Dale P. Cruikshank, Charles Elachi, Michael A. Janssen, Ralf Jaumann, Erich Karkoschka, Stéphane Le Mouélic, Rosaly Lopes, Ralph D. Lorenz, Thomas B. McCord, Philip D. Nicholson, Jani Radebaugh, Bashar Rizk, Christophe Sotin, Ellen R. Stofan, Tracie L. Sucharski, Martin G. Tomasko, Stephen D. Wall
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