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Caves as Terrestrial Analogs for Mapping and Exploration in Planetary Surface and Subsurface Environments.
The Kinematic Navigation and Cartography Knapsack (KNaCK) team is developing tools that will enable ultra-high resolution terrain mapping and navigation at the lunar surface. KNaCK uses mobile light detection and ranging (LiDAR) and simultaneous localization and mapping (SLAM) algorithms to operate in fully GPS-denied and unilluminated environments. Testing in relevant analogs is key to perfecting this technology for planetary applications. After utilizing desert and volcanic environments for multiple tests, the team is now using caves as an additional proving ground. Tests in terrestrial caves have demonstrated the potential of mobile SLAM LiDAR for use in challenging surface environments such as steep walled craters and permanently shadowed regions as well as for lunar, planetary, and terrestrial cave exploration, study, and utilization.
Landscape Water Storage and Subsurface Correlation From Satellite Surface Soil Moisture and Precipitation Observations
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The Viability of Glycine Fermentation in Titan’s Subsurface Ocean
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Spatial Scales and Time Variation of Solar Subsurface Convection
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Investigation of in situ physical properties of surface and subsurface site materials by engineering geophysical techniques Project quarterly report, 1 Oct. - 31 Dec. 1965
Physical properties of surface and near surface in situ material by engineering and geophysical techniques for possible lunar surface analogs
Investigation of in situ physical properties of surface and subsurface site materials by engineering geophysical techniques Annual report
Seismic energy spectrum and attenuation studied in Arizona geological formations for application to lunar surface investigations
Investigation of in situ physical properties of surface and subsurface site materials by engineering geophysical techniques Annual report, fiscal year 1965
Shear wave detection, wave amplitude, velocity, and attenuation in rock formations, seismic measurements, and geophysical studies analog to lunar geology
Investigation of in situ physical properties of surface and subsurface site materials by engineering geophysical techniques Annual report, fiscal year 1966
Density, moisture content, bearing capacity, shear strength, geology, and petrography of materials representative of lunar soil
Some factors affecting electromagnetic detection of lunar subsurface water.
Lunar surface pore water /or ice/ detection by active orbital or surface electromagnetic experiments, noting water effect on reflection coefficient
Cinemicrographic study of the development of subsurface colonies of Staphylococcus aureus in soft agar.
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Surface electrical properties experiment. Part 2: Theory of radio-frequency interferometry in geophysical subsurface probing
The radiation fields due to a horizontal electric dipole laid on the surface of a stratified medium were calculated using a geometrical optics approximation, a modal approach, and direct numerical integration. The solutions were obtained from the reflection coefficient formulation and written in integral forms. The calculated interference patterns are compared in terms of the usefulness of the methods used to obtain them. Scattering effects are also discussed and all numerical results for anisotropic and isotropic cases are presented.
Radar signal return from near-shore surface and shallow subsurface features, Darien Province, Panama
The AN/APQ-97 radar imagery over eastern Panama is analyzed. The imagery was directed toward extraction of geologic and engineering data and the establishment of operational parameters. Subsequent investigations emphasized landform identification and vegetation distribution. The parameters affecting the observed return signal strength from such features are considered. Near-shore ocean phenomena were analyzed. Tidal zone features such as mud flats and reefs were identified in the near range, but were not detectable in the far range. Surface roughness dictated the nature of reflected energy (specular or diffuse). In surf zones, changes in wave train orientation relative to look direction, the slope of the surface, and the physical character of the wave must be considered. It is concluded that the establishment of the areal extent of the tidal flats, distributary channels, and reefs is practical only in the near to intermediate range under minimal low tide conditions.