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Publications

Filter Total Items: 915

Physiography, Geomorphic/geologic Mapping and Stratigraphy of Venus

No abstract available.
Authors
K. L. Tanaka, D.A. Senske, M. Price, Randolph L. Kirk

The Topography of Asteroid Ida: A Comparison between Photogrammetric and Shape­Form-Shading Image Analysis

We derived high resolution Digital Terrain Models from stereo images of the asteroid Ida that were obtained by the Galileo spacecraft during the flyby in August 1993 and compared these results with terrain models derived from two-dimensional photoclinometry. The comparison shows that there are striking discrepancies between the results from the two models depending on the spatial scale length of s
Authors
Bernd Giese, Juergen Oberst, Randolph L. Kirk, W. Zeitler

Modeling of fluidized ejecta emplacement over digital topography on Venus

The FLOW computer model of McEwen and Malin (1989) modified for application to the study of Venus fluidized ejecta blankets (FEBs) demonstrates that relatively low viscosities, yield strengths, and initial velocities are required to duplicate the observed flow paths of the outflow materials. The model calculates the velocities and simulated flow paths of gravity flows over Magellan topography. The
Authors
Jeffrey R. Johnson, Lisa R. Gaddis

Decomposition of AVIRIS spectra: Extraction of spectral reflectance, atmospheric, and instrumental components

Presents techniques that use only information contained within a raw, high-spectral-resolution, hyperspectral Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) scene to estimate and remove additive components (atmospheric scattering and instrument dark current). These techniques allow normalization of multiplicative components (instrument gain, topography, atmospheric transmission) and enhan
Authors
Lisa R. Gaddis, Laurence A. Soderblom, Hugh H. Kieffer, Kris J. Becker, James M. Torson, Kevin F. Mullins

City of Flagstaff Project: Ground Water Resource Evaluation, Remote Sensing Component

Many regions, cities, and towns in the Western United States need new or expanded water resources because of both population growth and increased development. Any tools or data that can help in the evaluation of an area's potential water resources must be considered for this increasingly critical need. Remotely sensed satellite images and subsequent digital image processing have been under-utilize
Authors
Pat S. Chavez, Miguel G. Velasco, Jo-Ann Bowell, Stuart C. Sides, Rosendo R. Gonzalez, Deborah L. Soltesz

Water on early Mars

Large flood channels, valley networks and a variety of features attributed to the action of ground ice indicate that Mars emerged from heavy bombardment 3.8 Ga ago, with an inventory of water at the surface equivalent to at least a few hundred metres spread over the whole planet, as compared with 3 km for the Earth. The mantle of Mars is much drier than that of the Earth, possibly as a result of g
Authors
Michael D. Carr

Geology of 243 Ida

The surface of 243 Ida is dominated by the effects of impacts. No complex crater morphologies are observed. A complete range of crater degradation states is present, which also reveals optical maturation of the surface (darkening and reddening of materials with increasing exposure age). Regions of bright material associated with the freshest craters might be ballistically emplaced deposits or the
Authors
R. Sullivan, R. Greeley, R. Pappalardo, E. Asphaug, Johnnie N. Moore, D. Morrison, M. J. S. Belton, M. Carr, C. R. Chapman, Paul E. Geissler, R. Greenberg, J. Granahan, J. W. Head, Randolph L. Kirk, A. McEwen, P. Lee, P. C. Thomas, J. Veverka

A migratory mantle plume on Venus: Implications for Earth?

A spatially fixed or at least internally rigid hotspot reference frame has been assumed for determining relative plate motions on Earth. Recent 1:5,000,000 scale mapping of Venus, a planet without terrestrial-style plate tectonics and ocean cover, reveals a systematic age and dimensional progression of corona-like arachnoids occurring in an uncinate chain. The nonrandom associations between arachn
Authors
Mary G. Chapman, Randolph L. Kirk

Data base of impact craters on Venus based on analysis of Magellan radar images and altimetry data

No abstract available.
Authors
Gerald G. Schaber, Randolph L. Kirk, Robert G. Strom

Compositional variations on the Moon: Recalibration of Galileo solid‐state imaging data for the Orientale region and farside

Updated radiometric calibration and systematic processing procedures for Galileo solid‐state imaging (SSI) data from the first (1990) Earth‐Moon encounter are presented. These procedures were applied to a whole‐disk imaging sequence of the Moon centered near Mare Orientale, called Lunmap 14 (L14). Processing of L14 data included radiometric calibration, subpixel coregistration, scattered light rem
Authors
Lisa R. Gaddis, Alfred S. McEwen, Tammy L. Becker

Data base of impact craters on Venus based on analysis of Magellan radar images and altimetry data

No abstract available.
Authors
Gerald G. Schaber, Randolph L. Kirk, Robert G. Strom

Reply to comment on the global resurfacing of Venus

No abstract available.
Authors
R.G. Strom, G. G. Schaber, D.D. Dawson, Randolph L. Kirk