Dr. Walter S. Kiefer
Senior Staff Scientist
Dr. Walter Kiefer’s research focuses on the internal structure and evolution of the terrestrial planets and large icy satellites. One major area of interest is the thermal evolution of planets. His studies of mantle convection and tectonic features on Venus focus on understanding its apparent evolution from an Earth-like body with mobile lid convection in the past to a planet with a mostly stagnant surface at present, a transition which was likely caused by loss of liquid surface water. Other projects include studies of core formation and the early thermal evolution of asteroid 4 Vesta, modeling of mantle plume volcanism on Mars, and simulations of mantle convection on Io driven by tidal heating.
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 planets. He has used gravity observations to understand the subsurface magmatic plumbing of volcanic structures such as the Marius Hills and the Gruithuisen Domes on the Moon and Syrtis Major on Mars. 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 a Co-Investigator for the Deep Atmosphere Venus Investigation of Noble Gases, Chemistry, and Imaging (DAVINCI) mission, which will explore Venus in the late 2020s as part of NASA’s Discovery Program. He will lead studies of the rate of volcanic outgassing on Venus using mass spectrometer data and studies of the tectonics of the Alpha Regio landing site using descent imaging. In addition, he was a member of the Science Study Team that defined EnVision, a joint European Space Agency/NASA orbital remote sensing mission to Venus. Kiefer is also a Co-Investigator on the Gravity and Radio Science team for the Europa Clipper mission, focusing on determining local and regional structure in Europa’s ice shell. He was previously a member of the science team for NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission, which used high-resolution mapping of the Moon’s gravity field to determine the structure of the Moon’s crust and deep interior.Dr. Kiefer's personal webpage