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The roughness of natural terrain: A planetary and remote sensing perspective
We examine the various methods and parameters in common use for quantifying and reporting surface topographic “roughness.” It is shown that scale-dependent roughness parameters are almost alwaysExpand
Viking Lander image analysis of Martian atmospheric dust
We have reanalyzed three sets of Viking Lander 1 and 2 (VL1 and VL2) images of the Martian atmosphere to better evaluate the radiative properties of the atmospheric dust particles. The properties ofExpand
A test of the Hapke photometric model
[1] We conducted a test of the Hapke (1981, 1984, 1986, 2002) photometric model to determine what physical parameters could be confidently linked to a surface's photometric behavior. The first authorExpand
Mars Exploration Rover Athena Panoramic Camera (Pancam) investigation
[1] The Panoramic Camera (Pancam) investigation is part of the Athena science payload launched to Mars in 2003 on NASA's twin Mars Exploration Rover (MER) missions. The scientific goals of the PancamExpand
E‐type asteroid spectroscopy and compositional modeling
[1] We present near-infrared spectroscopic observations (0.8–2.5 μm) of E-type asteroids. We combine these observations with visible wavelength spectra obtained by other researchers and perform HapkeExpand
Near-Earth asteroid surface roughness depends on compositional class
Radar observations of 214 near-Earth asteroids (NEAs) reveal a very strong correlation of circular polarization ratio with visible-infrared taxonomic class, establishing distinct differences in theExpand
A radar survey of M- and X-class asteroids
Abstract We observed ten M- and X-class main-belt asteroids with the Arecibo Observatory's S-band (12.6 cm) radar. The X-class asteroids were targeted based on their albedos or other properties whichExpand
Radar Scattering from a Self-Affine Fractal Surface: Near-Nadir Regime
Abstract Planetary surfaces are better described by nonstationary fractal statistics than those more commonly assumed in current radar scattering models. Therefore, we have developed a radarExpand
Self‐affine (fractal) topography: Surface parameterization and radar scattering
Starting with the assumption that planetary surfaces are self-affine (fractal) over the scales applicable to radar scattering, we derive various surface parameters, e.g., rms slopes andExpand
Shadows on a Planetary Surface and Implications for Photometric Roughness
Abstract We advocate the use of fractal surface statistics as a simple, quantitative, and general model for planetary surface roughness. We determine the shadowing behavior of a wide range of fractalExpand