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Publications

Filter Total Items: 915

Determining Titan surface topography from Cassini SAR data

A technique, referred to as SARTopo, has been developed for obtaining surface height estimates with 10 km horizontal resolution and 75 m vertical resolution of the surface of Titan along each Cassini Synthetic Aperture Radar (SAR) swath. We describe the technique and present maps of the co-located data sets. A global map and regional maps of Xanadu and the northern hemisphere hydrocarbon lakes dis
Authors
Bryan W. Stiles, Scott Hensley, Yonggyu Gim, David M. Bates, Randolph L. Kirk, Alex Hayes, Jani Radebaugh, Ralph D. Lorenz, Karl L. Mitchell, Philip S. Callahan, Howard Zebker, William T.K. Johnson, Stephen D. Wall, Jonathan I. Lunine, Charles A. Wood, Michael Janssen, Frederic Pelletier, Richard D. West, Chandini Veeramacheneni

Relative age of interior layered deposits in southwest Candor Chasma based on high-resolution structural mapping

High‐resolution topography generated from stereo HiRISE (High‐Resolution Imaging Science Experiment) imagery reveals the meter‐scale structure of interior layered deposits (ILD) in southwest Candor Chasma. This study seeks to determine the age of the local ILD relative to any normal faults that can be attributed to chasma formation. The study area is located near the contact of these ILD and the w
Authors
Chris H. Okubo, Kevin W. Lewis, Alfred S. McEwen, Randolph L. Kirk

Surface processes recorded by rocks and soils on Meridiani Planum, Mars: Microscopic Imager observations during Opportunity's first three extended missions

The Microscopic Imager (MI) on the Mars Exploration Rover Opportunity has returned images of Mars with higher resolution than any previous camera system, allowing detailed petrographic and sedimentological studies of the rocks and soils at the Meridiani Planum landing site. Designed to simulate a geologist's hand lens, the MI is mounted on Opportunity's instrument arm and can resolve objects 0.1 m
Authors
Kenneth E. Herkenhoff, John P. Grotzinger, Andrew H. Knoll, Scott M. McLennan, Catherine M. Weitz, Aileen Yingst, Robert Anderson, Brent A. Archinal, Raymond E. Arvidson, Janet M. Barrett, Kris J. Becker, James F. Bell, Charles Budney, Mary G. Chapman, Debbie Cook, Bethany L. Ehlmann, Brenda Franklin, Lisa R. Gaddis, Donna M. Galuszka, Patricia A. Garcia, Paul E. Geissler, Trent M. Hare, Elpitha Howington-Kraus, Jeffrey R. Johnson, Laszlo P. Keszthelyi, Randolph L. Kirk, Peter Lanagan, Ella M. Lee, Craig Leff, Justin N. Maki, Kevin F. Mullins, Timothy J. Parker, Bonnie L. Redding, Mark R. Rosiek, Michael H. Sims, Laurence A. Soderblom, Nicole Spanovich, Richard Springer, Steven W. Squyres, Daniel A. Stolper, Robert M. Sucharski, Tracie L. Sucharski, Robert Sullivan, James M. Torson

In-situ observations of the physical properties of the Martian surface

The physical properties of rocks and soils on the surface of Mars have been investigated by several landed spacecraft. Studies of these physical properties constrain interpretation of Martian geologic processes and provide engineering data for future mission planning. As on Earth, these properties vary considerably from place to place, and provide constraints on the origin and evolution of the sur
Authors
Kenneth E. Herkenhoff, M. P. Golombek, E.A. Guinness, J.B. Johnson, A. Kusack, L. Richter, R.J. Sullivan, S. Gorevan

First in situ investigation of a dark wind streak on Mars

Prominent low‐albedo wind streaks issue from embayments at the north end of Victoria crater in Meridiani Planum, the site of surface investigations by the Mars Exploration Rover Opportunity. Opportunity was sent to examine the darkest of these wind streaks and compare it to the adjacent soil in the brighter corridor between the streaks. Two nearby sites inside and outside of the streak were select
Authors
Paul E. Geissler, J. R. Johnson, R. Sullivan, Kenneth E. Herkenhoff, D. W. Mittlefehldt, Robin L. Fergason, D. Ming, R. Morris, S. Squyres, Laurence A. Soderblom, M. Golombek

Spirit Mars Rover Mission to the Columbia Hills, Gusev Crater: Mission overview and selected results from the Cumberland Ridge to Home Plate

This paper summarizes the Spirit rover operations in the Columbia Hills of Gusev Crater from sols 513 to 1476 and provides an overview of selected findings that focus on synergistic use of the Athena Payload and comparisons to orbital data. Results include discovery of outcrops (Voltaire) on Husband Hill that are interpreted to be altered impact melt deposits that incorporated local materials duri
Authors
R. E. Arvidson, S. W. Ruff, R.V. Morris, D. W. Ming, L.S. Crumpler, A. S. Yen, S. W. Squyres, R.J. Sullivan, J.F. Bell, N.A. Cabrol, B. C. Clark, W. H. Farrand, R. Gellert, R. Greenberger, J. A. Grant, E.A. Guinness, Kenneth E. Herkenhoff, J.A. Hurowitz, J. R. Johnson, G. Klingelhoefer, K. W. Lewis, R. Li, T.J. McCoy, J. Moersch, H.Y. McSween, S.L. Murchie, M. Schmidt, C. Schroeder, A. Wang, S. Wiseman, M.B. Madsen, W. Goetz, S. M. McLennan

First in situ investigation of a dark wind streak on Mars

[1] Prominent low-albedo wind streaks issue from embayments at the north end of Victoria crater in Meridiani Planum, the site of surface investigations by the Mars Exploration Rover Opportunity. Opportunity was sent to examine the darkest of these wind streaks and compare it to the adjacent soil in the brighter corridor between the streaks. Two nearby sites inside and outside of the streak were se
Authors
Paul E. Geissler, J.R. Johnson, R. Sullivan, Kenneth E. Herkenhoff, K Mittlefeldt, Robin L. Fergason, D. W. Ming, R. I. G. Morrison, S. W. Squyres, Laurence A. Soderblom, M. P. Golombek

Implications for Martian polar processes, Ch. 25

No abstract available.
Authors
Timothy N. Titus, W. M. Calvin, H. H. Kieffer, Yves Langevin, Thomas H. Prettyman

Titan's rotation reveals an internal ocean and changing zonal winds

Cassini radar observations of Saturn's moon Titan over several years show that its rotational period is changing and is different from its orbital period. The present-day rotation period difference from synchronous spin leads to a shift of ∼0.36° per year in apparent longitude and is consistent with seasonal exchange of angular momentum between the surface and Titan's dense superrotating atmospher
Authors
Ralph D. Lorenz, Bryan W. Stiles, Randolph L. Kirk, Michael D. Allison, Paolo Persi del Marmo, Luciano Iess, Jonathan I. Lunine, Steven J. Ostro, Scott Hensley

Introduction to planetary and space science special issue: Mars polar processes

No abstract available.
Authors
Timothy N. Titus, Anthony Colaprete, Thomas H. Prettyman

Geology and Surface Processes on Titan

The surface of Titan has been revealed globally, if incompletely, by Cassini observations at infrared and radar wavelengths as well as locally by the instruments on the Huygens probe. Extended dune fields, lakes, mountainous terrain, dendritic erosion patterns and erosional remnants indicate dynamic surface processes. Valleys, small-scale gullies and rounded cobbles such as those observed at the H
Authors
Ralf Jaumann, Randolph L. Kirk, Ralph D. Lorenz, Rosaly M.C. Lopes, Ellen Stofan, Elizabeth P. Turtle, Horst Uwe Keller, Charles A. Wood, Christophe Sotin, Laurence A. Soderblom, Martin G. Tomasko

HiRISE observations of fractured mounds: Possible Martian pingos

Early images from the High Resolution Imaging Science Experiment (HiRISE) camera have revealed small fractured mounds in the Martian mid‐latitudes. HiRISE resolves fractures on the mound surfaces, indicating uplift, and shows that the mound surface material resembles that of the surrounding landscape. Analysis of Mars Orbiter Camera (MOC) images shows that in Utopia Planitia the mounds lie almost
Authors
Colin M. Dundas, Michael T. Mellon, Alfred S. McEwen, Alexandra Lefort, Laszlo P. Keszthelyi, Nicolas Thomas