Dr. Walter S. Kiefer
Dr. Walter Kiefer's research focuses on the internal structure and evolution of the Moon, Mars, Venus, and differentiated meteorite parent bodies. One major area of interest is the thermal evolution of planets. His studies of Mars include simulations of magma production in mantle plumes, which are the likely cause of the geologically recent volcanism in places such as Olympus Mons. He also models the long-term thermal evolution of Mars, with a focus on the crustal production rate, the mantle degassing history, and the history of the core’s magnetic dynamo. This research primarily involves computer modeling. The model results are tested by comparison with observations of gravity, topography, surface imagery, and magnetic fields obtained by NASA planetary spacecraft missions and by geochemical observations of the martian meteorites. He studies the differentiation, thermal evolution, and magmatic history of asteroid 4 Vesta and magma production and rifting associated with mantle plumes on Venus.
The second main emphasis of Dr. Kiefer's research is using gravity and topography observations to study the structure of the crust and lithosphere of the terrestrial planets. He was a member of the science team for NASA’s GRAIL mission, which produced a very high resolution (~ 5 km/pixel) map of the Moon’s gravity field. He uses GRAIL gravity observations to understand the volcanic structure and subsurface plumbing of features such as the Gruithuisen Domes and the Marius Hills. He also uses gravity and topography observations to study the evolution of Mars, with a particular focus on large highland volcanos such as Syrtis Major and Apollinaris Mons. In support of these projects, he has measured the density and porosity of lunar and martian rocks using laser scanning and helium pycnometry in the Lunar Sample Laboratory and the Antarctic Meteorite Laboratory at NASA’s Johnson Space Center.
Dr. Kiefer is actively involved in a variety of science education programs. He has contributed to numerous summer teacher training workshops, including several that have been based at field sites in the western United States that serve as analogs for processes on the terrestrial planets (including the Channeled Scablands, the Columbia River flood basalts, Yellowstone, the Snake River Plains, the Cascade volcanos, Meteor Crater, and Mono Lake). He has also contributed to the development of a variety of educational products designed for use in either formal classroom settings or in informal education settings such as libraries.