Publications

The Mairan domes are four features located in northern Oceanus Procellarum at ∼312.3E, 41.4N on the Moon. High resolution visible imagery, visible-to-mid-IR spectra, and Lunar Prospector Th abundance data all indicate that these four domes have a composition that is consistent with derivation from a Si-rich, highly evolved magma.

The presence of outcrops and soil (regolith) rich in opaline silica (∼65–92 wt % SiO2) in association with volcanic materials adjacent to the “Home Plate” feature in Gusev crater is evidence for hydrothermal conditions. The Spirit rover has supplied a diverse set of observations that are used here to better understand the formation of silica and the activity, abundance, and fate of water...

Structural geology is an integral part of planetary science. Planetary structures provide the framework for determining the character and sequence of crustal deformation while simultaneously establishing the observational basis required to test geodynamic hypotheses for the deformation of planetary and satellite lithospheres. The availability of datasets that record spatial and...

Every three years the IAU Working Group on Cartographic Coordinates and Rotational Elements revises tables giving the directions of the poles of rotation and the prime meridians of the planets, satellites, minor planets, and comets. This report takes into account the IAU Working Group for Planetary System Nomenclature (WGPSN) and the IAU Committee on Small Body Nomenclature (CSBN)...

The Lunar Reconnaissance Orbiter Camera (LROC) is systematically imaging impact melt deposits in and around lunar craters at meter and sub-meter scales. These images reveal that lunar impact melts, although morphologically similar to terrestrial lava flows of similar size, exhibit distinctive features (e.g., erosional channels). Although generated in a single rapid event, the post-impact...

We report the identification of compounds on Titan's surface by spatially resolved imaging spectroscopy methods through Titan's atmosphere, and set upper limits to other organic compounds. We present evidence for surface deposits of solid benzene (C6H6), solid and/or liquid ethane (C2H6), or methane (CH4), and clouds of hydrogen cyanide (HCN) aerosols using diagnostic spectral features...

We provide an overview of features indicative of the interaction between water and lava and/or magma on Mars as seen by the High Resolution Imaging Science Experiment (HiRISE) camera during the Primary Science Phase of the Mars Reconnaissance Orbiter (MRO) mission. The ability to confidently resolve meter-scale features from orbit has been extremely useful in the study of the most...

On September 4, 2007, after 25 years of effusive natrocarbonatite eruptions, the eruptive activity of Oldoinyo Lengai (OL), N Tanzania, changed abruptly to episodic explosive eruptions. This transition was preceded by a voluminous lava eruption in March 2006, a year of quiescence, resumption of natrocarbonatite eruptions in June 2007, and a volcano-tectonic earthquake swarm in July 2007...

Ontario Lacus is the largest and best characterized lake in Titan's south polar region. In June and July 2009, the Cassini RADAR acquired its first Synthetic Aperture Radar (SAR) images of the area. Together with closest approach altimetry acquired in December 2008, these observations provide a unique opportunity to study the lake's nearshore bathymetry and complex refractive properties...

The Mars Global Digital Dune Database presents data and describes the methodology used in creating the global database of moderate- to large-size dune fields on Mars. The database is being released in a series of U.S. Geological Survey (USGS) Open-File Reports. The first release (Hayward and others, 2007) included dune fields from 65 degrees N to 65 degrees S (http://pubs.usgs.gov/of...

Present‐day accumulation in the north polar layered deposits (NPLD) is thought to occur via deposition on the north polar residual cap. Understanding current mass balance in relation to current climate would provide insight into the climatic record of the NPLD. To constrain processes and rates of NPLD resurfacing, a search for craters was conducted using images from the Mars...

We investigate a spectrum-based technique to identify the style of active volcanic eruptions on Jupiter's moon Io. Thermal remote sensing of Io has had to rely primarily on low-spatial-resolution data, similar to low-spatial-resolution satellite data applied to detecting and charting the temporal evolution of terrestrial hot spots. These terrestrial analyses use data from sensors...