particles detector on NASA’s Galileo spacecraft, and the energetic particle detector and ion composition experiment on the Japanese/NASA Geotail satellite.
Roger V.Yelle is associate professor in the Department of Physics and Astronomy at Northern Arizona University. Dr. Yelle studies atmospheres and icy surfaces in this solar system and the atmospheres of extrasolar planets. He analyzes telescopic and spacecraft data and constructs theories and models to determine the composition and structure of atmospheres and their interaction with surfaces. His current projects include the following: the structure of extrasolar, Jupiterlike planets; thermal modeling of the energetics of the Jovian stratosphere and upper atmosphere in order to determine the importance of radiative and dynamical processes, and the relationship between composition and thermal structure; and analysis of the ultraviolet spectra of Jupiter in order to constrain the abundance of aerosols and hydrocarbons and to understand the role of Raman scattering. Dr. Yelle also works on NASA planetary missions, and he is a team member on the Ion Neutral Mass Spectrometer experiment on the Cassini mission to the Saturn system. He is also a member of the Miniature Integrated Camera Spectrometer team on NASA’s Deep Space 1 mission to an asteroid and a comet. Dr. Yelle is a member of the American Geophysical Union, American Astronomical Society, and European Geophysical Society. He is a former member of the National Research Council’s Committee on Planetary and Lunar Exploration.
James R.Zimbelman is a geologist for the Center for Earth and Planetary Studies, National Air and Space Museum (NASM), Smithsonian Institution. His main area of expertise is planetary geology, with emphasis on the analysis of high-resolution remote sensing and imaging data of Mars, geologic mapping of Mars and Venus, computer simulations of lava flows, and field studies of volcanic and aeolian features. He has been curator for “Exploring the Planets” (NASM Gallery 207) since March 1998. Prior to his position at the Smithsonian, Dr. Zimbelman was staff scientist at the Lunar and Planetary Institute. His many honors and activities include the following: chairman, Planetary Geology and Geophysics Review Panel, NASA, 1997–1999; NASA Venus Data Analysis Program Review Panel, 1992; and chairman, Regional Planetary Image Facility Directors and Data Managers Group, NASA, 1994–1997. Dr. Zimbelman is a fellow of the Geological Society of America, and member of the American Geophysical Union and the Geological Society of America.