Publications
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RADAR: The Cassini Titan Radar Mapper
The Cassini RADAR instrument is a multimode 13.8 GHz multiple-beam sensor that can operate as a synthetic-aperture radar (SAR) imager, altimeter, scatterometer, and radiometer. The principal objective of the RADAR is to map the surface of Titan. This will be done in the imaging, scatterometer, and radiometer modes. The RADAR altimeter data will provide information on relative elevations in selecte
Authors
C. Elachi, M.D. Allison, L. Borgarelli, P. Encrenaz, E. Im, M.A. Janssen, W.T.K. Johnson, Randolph L. Kirk, R. D. Lorenz, J. I. Lunine, D.O. Muhleman, S.J. Ostro, G. Picardi, F. Posa, C.G. Rapley, L.E. Roth, R. Seu, Laurence A. Soderblom, S. Vetrella, S. D. Wall, C. A. Wood, H. A. Zebker
The face of the Moon: Lunar volcanoes and volcanic deposits
No abstract available.
Authors
Lisa R. Gaddis
Exploring Martian polar atmospheric circulation and surface interactions
The northern and southern seasonal polar caps of Mars are formed in the polar night, during their respective autumn and winter seasons, by the condensation of atmospheric CO2directly to the solid phase as ice, snow, and possibly frost. During spring and summer, the seasonal ice sublimes, returning CO2 to the atmosphere. The caps advance and recede in response to seasonal variations in solar insola
Authors
Thomas H. Prettyman, Timothy N. Titus
Textures of the soils and rocks at Gusev Crater from Spirit’s Microscopic Imager
The Microscopic Imager on the Spirit rover analyzed the textures of the soil and rocks at Gusev crater on Mars at a resolution of 100 micrometers. Weakly bound agglomerates of dust are present in the soil near the Columbia Memorial Station. Some of the brushed or abraded rock surfaces show igneous textures and evidence for alteration rinds, coatings, and veins consistent with secondary mineralizat
Authors
Kenneth E. Herkenhoff, S. W. Squyres, R. Arvidson, D.S. Bass, J. F. III Bell, P. Bertelsen, N.A. Cabrol, Lisa R. Gaddis, A. G. Hayes, S.F. Hviid, J. R. Johnson, K.M. Kinch, M.B. Madsen, J.N. Maki, S. M. McLennan, H.Y. McSween, J. W. Rice, M. Sims, P. H. Smith, Laurence A. Soderblom, Nicole Spanovich, R. Sullivan, A. Wang
Magnetic properties experiments on the Mars Exploration Rover Spirit at Gusev Crater
The magnetic properties experiments are designed to help identify the magnetic minerals in the dust and rocks on Mars—and to determine whether liquid water was involved in the formation and alteration of these magnetic minerals. Almost all of the dust particles suspended in the martian atmosphere must contain ferrimagnetic minerals (such as maghemite or magnetite) in an amount of ∼2% by weight. Th
Authors
P. Bertelsen, W. Goetz, M.B. Madsen, K.M. Kinch, S.F. Hviid, J. M. Knudsen, H.P. Gunnlaugsson, J. Merrison, P. Nørnberg, S. W. Squyres, J. F. III Bell, Kenneth E. Herkenhoff, S. Gorevan, A. S. Yen, T. Myrick, G. Klingelhoefer, R. Rieder, R. Gellert
Topographic mapping of Mars: From hectometer to micrometer scales
We describe USGS topomapping of Mars at resolutions from 100 m to 30 µm with data from the latest spacecraft missions. Analysis of NASA 2001 Mars Odyssey Thermal Emission Imaging System (THEMIS) data combining daytime visible reflected, daytime IR emitted, and nighttime IR emitted images allows us to isolate the physical effects of topography, albedo, and thermal inertia. To a good approximation t
Authors
Randolph L. Kirk, Steven W. Squyres, Gerhard Neukum
A new Mars Digital Image Model (MDIM 2.1) control network
The U.S. Geological Survey has recently completed a final revised version of its 231 m/pixel global Viking image mosaic of Mars that has substantially improved geodetic accuracy compared to versions released in 1991 and 2001. This mosaic, known as MDIM 2.1, is currently available in the USGS ISIS file format (see http://astrogeology.usgs.gov/Projects/MDIM21/) and will be formatted and submitted to
Authors
Brent A. Archinal, Ella M. Lee, Randolph L. Kirk, T. C. Duxbury, Robert M. Sucharski, Debbie Cook, Janet M. Barrett
A new Mars Digital Image Model (MDIM 2.1) control network
The U.S. Geological Survey has recently completed a final revised version of its 231 m/pixel global Viking image mosaic of Mars that has substantially improved geodetic accuracy compared to versions released in 1991 and 2001. This mosaic, known as MDIM 2.1, is currently available in the USGS ISIS file format and will be formatted and submitted to the NASA Planetary Data System (PDS) in the near fu
Authors
Brent A. Archinal, Ella M. Lee, Randolph L. Kirk, T. C. Duxbury, Robert M. Sucharski, Debbie Cook, Janet M. Barrett
The emplacement of pahoehoe toes: Field observations and comparison to laboratory simulations
We observed active pahoehoe lobes erupted on Kilauea during May-June 1996, and found a range of emplacement styles associated with variations in local effusion rate, flow velocity, and strain rate. These emplacement styles were documented and quantified for comparison with earlier laboratory experiments.At the lowest effusion rates, velocities, and strain rates, smooth-surfaced lobes were emplaced
Authors
Tracy K. P. Gregg, Laszlo P. Keszthelyi
Io after Galileo
No abstract available.
Authors
Elizabeth P. Turtle, Laszlo P. Keszthelyi, David A. Williams
Mars: Water, water everywhere
Mars is a very watery planet, but all the water seems to be frozen. Divining the amount and distribution of this water, past and present, is essential for understanding martian climates, and more.
Authors
Timothy N. Titus
Preparing for THEMIS controlled global Mars mosaics
We have begun work to prepare for producing controlled 2001 Mars Odyssey THEMIS infrared (IR) and visible (VIS) global mosaics of Mars. This effort is being coordinated with colleagues from Arizona State University and on the THEMIS team who plan to address radiometric issues in making such mosaics. We are concentrating on geometric issues. Several areas of investigation are now in progress, inclu
Authors
Brent A. Archinal, Lynn A. Weller, Stuart C. Sides, Glen E. Cushing, Randolph L. Kirk, Laurence A. Soderblom, T. C. Duxbury