Geomorphology

The USGS Astrogeology Science Center conducts research on the interaction between planetary surfaces and the overlying atmospheres. In particular, the transfer of momentum (from wind), vapor (evaporation/sublimation), liquid (rainfall, percolation, infiltration) and solids (snow) occurs between surfaces and atmospheres.

The U. S. Geological Survey (USGS) Astrogeology Science Center (ASC) recently established the Terrestrial Analogs for Research and Geologic Exploration Training (TARGET) program. This service-oriented program is built around the recognition that the Earth is a fundamental training ground for human and robotic planetary exploration, and that ASC is in a unique position in northern Arizona with...

Sand dunes are among the most widespread aeolian features present on Mars, serving as unique indicators of the interaction between the atmosphere and surface. On a planetary body, dunes accumulate where a supply of sand-sized grains exists or may be abraded, is carried downwind by winds of saltation strength, and is subsequently deposited where these winds weaken below the threshold for sand...

The Cassini RADAR team led by USGS scientist, Randolph Kirk , has discovered the "best candidate yet" for an ice volcano on Saturn's moon Titan. The 3D view reveals multiple mountain peaks, deep pits and finger-like flows at Sotra Facula. Some of the terrain resembles volcanic cones, craters and flows on Earth but made of Titan materials (ice and/or carbon compounds) not molten rock. Existence of...

The Valles Marineris is a system of canyons located just south of the Martian equator. The system is about 4000 km long, and, if on earth, would extend all the way across the United States. The central individual troughs, generally 50 to 100 km wide, merge into a depression as much as 600 km wide. In places the canyon floor reaches a depth of 10 km, 6 to 7 times deeper than the Grand Canyon.

The NASA Magellan spacecraft provided synthetic aperture radar (SAR) image coverage of 98% of the surface of the planet Venus, in addition to topography and several types of physical property data on the venusian surface (e.g., radar reflectivity, radar backscatter, emissivity, and rms slopes).(See Special Magellan Issue of J. Geophys. Res., v. 97, nos. E8 and E10, August 25 and Sept. 25, 1992.)...

The Astrogeology Team at USGS provides coordination of NASA's planetary geologic mapping program. Geologic mapping investigations of any imaged planetary body (except Earth) are proposed to NASA's Planetary Geology and Geophysics Program on an annual basis (generally due sometime between late April and early June) and then reviewed by the Lunar and Planetary Geoscience Review Panel. USGS map...