My research program focuses on quantitative investigations of an array of geological and geophysical processes on Earth and planetary surfaces throughout the solar system (cryospheres, geomorphology, thermophysics, volatiles, climate change, surface-atmosphere interactions, and regoliths) employing a full spectrum of theoretical modeling, laboratory experiments, terrestrial field work, and spacecraft operations and data analysis. Relative proportions vary with typically 1/3 in each of theoretical, laboratory, and data analysis areas integrated with fieldwork. I am also an active science team member with multiple current and future NASA flight missions to Mars and Europa, utilizing remote sensing techniques of visible imaging, ground penetrating radar, and thermal infrared emission. My focus is on addressing fundamental science questions, interpreting remote-sensing data, characterizing planetary surfaces, and comparing similar processes between planets.
- Weathering processes and regolith development (Moon, icy Galilean moons).
- Ground-ice stability (Mars, Antarctica): Theoretical modeling and remote sensing.
- Periglacial landforms (Mars, Antarctica): Geomorphology, geophysical processes, climate conditions, modeling formation rates and landform characteristics.
- Climate change (Mars, Antarctica): Evidence from ground ice and periglacial landforms.
- Ice/volatile processes in the solar system: Stability and sublimation terrains of non-water ices.
- Thermophysics of soils (Mars, Moon, Earth, and Europa): Laboratory measurements; thermal properties of minerals, rocks, and soils; spacecraft data analysis.
- Gas and water transport within soils (Antarctic, Mars): laboratory measurements; structure of ice in permafrost; physical properties of soils.
- Dielectric properties of soils and permafrost (Earth, Mars): Ground penetrating radar.
- Mechanical strength and cohesion in soils (Earth, Mars, Moon).
- Geologic fieldwork and field data analysis in Antarctica and Alaska, examining Antarctic periglacial processes, terrestrial planetary-analog sites, and Arctic soils.
Major Experimental Areas:
- Thermal properties of soils, rocks, and minerals.
- Gas diffusion through soils and porous media.
- Ice processes in soils.
- Dielectric and magnetic properties of materials.
- Mechanical strength of soils and granular materials.
Flight Mission Activities:
- 2016-present Science Co-I, Europa 2022 “Clipper” , Europa Thermal Emission Imaging System (E-THEMIS)
- 2014-present Science Co-I, Mars 2020, Radar Imager for Mars Subsurface Experiment (RIMFAX)
- 2002-present Science Team and Affiliate, Mars Reconnaissance Orbiter, Shallow Radar (SHARAD)
- 2001-present Science Co-I, Mars Reconnaissance Orbiter, High Resolution Image Science Experiment (HiRISE)
- 2003-2009 Science Co-I, Mars Scout Phoenix, Interdisiplinary Scientist, Geology Lead, Stratigic Planning Lead
- 2001-2002 Science Affiliate, Mars Odyssey THEMIS
- 1997-2002 Science Affiliate, Mars Global Surveyor, Thermal Emission Spectrometer (TES),
- 1996 Science Affiliate, Mars ’96 Mars Oxidant Experiment (MOx)