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Publications

Filter Total Items: 910

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

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

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

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

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

Velocities and mass balance of Pine Island Glacier, West Antarctica, derived from ERS-1 SAR images

Pine Island Glacier is one of the major ice streams draining West Antarctica. We calculated average velocities for both its grounded and floating parts by tracking crevasses and other patterns moving with the ice on two sequential images acquired in February and December 1992 by ERS-1 SAR (European Remote-Sensing Satellite, Synthetic Aperture Radar). Velocities in the fast-moving central parts of
Authors
Baerbel K. Lucchitta, Christina E. Rosanova, K.F. Mullins

Geology of Triton

Triton, with a diameter of ≡2700 km, is Neptune's only planet-class satellite. The complexity of Triton's surface and the variety of surface features is unequaled among the satellites of the solar system. From a geologic viewpoint, some of Triton's features have apparently familiar morphologies and general interpretative agreement exists. However, many of its landforms have novel morphologies and
Authors
S.K. Croft, J.S. Kargel, Randolph L. Kirk, J.M. Moore, P.M. Schenk, R.G. Strom

Triton's plumes: Discovery, characteristics, and models

This chapter presents (1) basic observations and characteristics of Triton's plumes (scale, geometry, optical properties, and temporal behavior); (2) the current best estimates of other parameters that can be derived directly or inferred from the observations (plume duration, wind velocities, particle properties, mass fluxes, energy requirements, and total erupted mass); and (3) a discussion of va
Authors
Randolph L. Kirk, Laurence A. Soderblom, R. H. Brown, S. W. Kieffer, J.S. Kargel

Venus cartography

The entire surface of the planet Venus is being mapped at global and regional scales (1:50,000,000 through 1:1,500,000) with synthetic aperture radar (SAR), radar altimeter, and radiometer measurements of physical properties from the Magellan spacecraft. The mapping includes SAR image mosaics, shaded relief maps, and topographic contour overlays made from altimetry data and by radargrammetric meth
Authors
R. M. Batson, Randolph L. Kirk, Kathleen Edwards, H.F. Morgan

Evaluation of an empirical radar backscatter model for predicting backscatter characteristics of geologic units at Pisgah Volcanic Field, California

Comparison of radar backscatter coefficients (σ°, in dB), calculated by using the empirical model of Oh et al. [1992], to σ° extracted from AIRSAR data of four geologic units at Pisgah shows that the model predicts measured σ°vv and σ°hv to within ±3 dB. The model predicts higher σ°hh than those observed. For smooth surfaces (rms height=s, s<8 cm), model results depend strongly on the accuracy of
Authors
Lisa R. Gaddis