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Photo of Kathie Thomas-Keprta KATHIE THOMAS-KEPRTA

Kathie Thomas-Keprta has been working with Lockheed Martin for 15 years as a Senior Scientist. Previous education includes an MS in Biochemistry from Texas Woman's University with an undergraduate degree in Biochemistry from the University of Illinois. Although Lockheed does not designate her specific area of research, in reality Kathie is a Planetary Geologist examining extraterrestrial materials in the form of meteorites and Interplanetary Dust Particles or IDPs. Kathie initially began her work with IDPs; these are thought to be samples of asteroids and comets and are therefore some of the most primitive materials in our solar system available for study. Kathie has published over 100 papers on the mineralogical compositions of these small particles. Kathie continued her research with the study of meteorites and that led to the study of the planet Mars. Kathie works with very small amounts of material; most samples are in the 20-50 micrometer size range. Kathie prepares these particles for study using ultramicrotomy and transmission electron microscopy and determines the chemical and minerological composition of the mineral grains within these samples.

The study of Martian meteorite ALH84001 has been some of her most rewarding work. It has taken over five years to determine the mineralogical composition of some components of this unique meteorite. The presence of tiny mineral grains called magnetite in the mars meteorite may be some of the strongest evidence of possible ancient Martian life in the form of bacteria. Her team is one of the founding members of the new Astrobiology Institute, established in 1998, and will continue to work on determining the presence/absence of biomarkers (biological fingerprints) in terrestrial and extraterrestrial materials.

The main goal of the team at Johnson Space Center will be to define a set of biomarkers that may be applied to the first samples returned from Mars, scheduled at this time for the year 2008. There is a robust schedule for Mars exploration established by NASA and these missions will lead to a greater understanding of Mars and whether or not life existed in the early years of the planet (approximately 3-4.5 billion years ago) and if life exists under the surface of the planet today.

See Kathie Thomas-Keprta's answers to Ask the Scientists questions.


Scientific American Frontiers
Fall 1990 to Spring 2000
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