DR. DAVID MITTLEFEHLDT, affectionately known far and wide as "Duck," is a scientist in the Astromaterials Research Office at NASA Johnson Space Center (JSC). He spends his time pursuing research on the formation of meteorites and how they relate to the early history of the solar system. His major interests are achondrite and stony iron meteorites-those meteorites that have been heated enough to have suffered incipient or full-blown igneous processing-and Martian meteorites. He studies the petrology and geochemistry of these materials using electron microprobe analyses of minerals in thin section, instrumental neutron activation analyses of bulk samples, and a pot of coffee to defog the brain.

Duck earned a BS in Geology from SUNY College at Fredonia in 1973, and a Ph.D. in Geochemistry from UCLA in 1978. At UCLA, quite by chance, he began his long, intimate association with meteorites. There he worked on the origin of basaltic achondrites and mesosiderites in the research group led by Prof. John T. Wasson. With degree in hand, he then sojourned far and wide through many research, academic and governmental institutions. Finally, in 2000, he was hired by NASA JSC as a space scientist where he manages the neutron activation analysis laboratory.

Duck was a team member on the 1997 and 2001 Antarctic Search for Meteorites (ANSMET) field teams. He was an Associate Editor for Geochimica et Cosmochimica Acta from 1992 to 1997, and has been an Associate Editor for Meteoritics and Planetary Science since 1998. He was on the editorial board of the Macmillan Encyclopedia of Earth Sciences that was published in 1996. He served on NASA's Lunar and Planetary Geoscience (now called the Cosmochemistry Program) Review Panel. He was a co-convener of a workshop sponsored by the Lunar and Planetary Institute entitled "Evolution of Igneous Asteroids: Focus on 4 Vesta and the HED Meteorites." He served as Acting Meteorite Curator for NASA/JSC in 2001, and is a Principle Investigator in NASA's Cosmochemistry Program. He has published extensively on the petrology and geochemistry of meteorites and a selection of his recent research can be found at http://ares.jsc.nasa.gov/mittlefehldt/.