Gero Kurat (1938–2009)

Abstract

Gero Kurat, the former head of the Mineralogical-Petrographical Department and curator of the meteorite collection at the Natural History Museum in Vienna, Austria, died on November 27, 2009, at the age of 71. Gero was a pioneer in meteorite research, a gifted mineralogist, petrologist, and geochemist. He was among the first meteorite researchers to combine petrographic observations of meteorite textures with quantitative electron microprobe analyses. But he also made important contributions to the chemistry and mineralogy of lunar and terrestrial rocks. In 1999 and 2000, Gero Kurat was vice president and in 2001 and 2002, president of the Meteoritical Society. Gero Kurat was born on November 18, 1938, in Klagenfurt, Austria. He studied petrology at the University of Vienna, where he received his Ph.D. in 1963. In 1962, Gero entered the Natural History Museum, Vienna (NHMV) as a volunteer and was appointed custodian at the Mineralogical-Petrographical Department in 1963. From 1968 until his retirement in 2003, he was head of the Mineralogical-Petrographical Department and curator of the meteorite collection of the NHMV—an almost peerless tenure. During his directorship, the department evolved from a historical repository for meteorites to a world-wide known research institution focusing on meteorite and planetary research, competing with the best foreign university departments and research institutions in this area. Despite chronic financial shortages, Gero managed to expand the collections with innovative funding arrangements and also acquire the necessary research equipment that allowed him to do high-class research participating with his staff in international research programs, such as the study of lunar rocks and interplanetary dust particles. Gero Kurat also realized early on that he had to go abroad to learn the newest developments in the research of extraterrestrial materials. In 1966, he spent 3 months at the Smithsonian Institution, Washington, D.C., to work on meteorites. After returning from the USA, Gero wrote a remarkable set of papers on chondrules and matrix of chondritic meteorites. During this time, he encountered strange inclusions with Ca, Al-rich minerals almost free of iron in the Lancé meteorite. At the same time, Mireille Christophe Michel-Levy from Paris had found similar objects in the Vigarano meteorite. Apparently Mireille Christophe Michel-Levy and Gero Kurat were among the first to study Ca, Al-rich inclusions (CAIs) in meteorites. It was the beginning of a rapidly expanding research area that still produces new surprises, almost annually. Mireille Christophe Michel-Levy interpreted the Ca, Al-inclusions as high temperature condensates, while Gero Kurat suggested evaporation of chrondritic matter as the mechanism for enrichment of refractory elements. This is a still ongoing debate. As Mireille Christophe Michel-Levy wrote in French and Gero Kurat in German, their papers are today almost forgotten. In 1970/1971, Gero Kurat took leave of absence from the museum to study the mineralogy and petrology of meteorites and lunar rocks with Klaus Keil at the Institute of Meteoritics in Albuquerque, New Mexico. In addition, Gero wanted to learn the use of the electron microprobe, in preparation for his eventual purchase of such an instrument in Vienna. With Klaus Keil and his group Gero worked on the returned lunar samples, during the height of the Apollo area. While staying at UNM, Gero and his family traveled extensively within the USA. After his return from the USA, Gero succeeded in acquiring an ARL electron microprobe for the Natural History Museum. At about the same time, Georg Hoinkes, now professor of petrology at the University of Graz and later Alfred Kracher, now a well-known meteorite researcher, joined Gero’s group. With the new microprobe, Gero began to study upper mantle rocks from the Earth, such as spinel-lherzolitic xenoliths from volcanics in Kapfenstein, southern Austria and peridotites from Zabargad Island. The emphasis of this research was the attempt to understand the composition and mineralogy of the Earth’s mantle within the framework of primitive meteorite compositions—a project in the new field of comparative planetology. He also continued the study of lunar rocks by investigating mainly samples from the Luna 20 and 24 missions. To complement his mineralogical analyses with bulk chemical analyses, Gero began to work together with the cosmochemistry department at the Max-Planck-Institute for Chemistry in Mainz. This was the beginning of a long and fruitful cooperation that resulted in many papers on meteorites and upper mantle rocks. For more than one decade, Gero was involved in studies of the mineral chemistry of different uranium mineralizations from all over the world, resulting in numerous internal reports for the International Atomic Energy Agency (IAEA) up to the mid-1980s. In 1976, he received his “venia legendi,” allowing him to teach and supervise graduate students at the University of Vienna. In 1977, he was a visiting professor at the University in Sao Paulo, Brazil. In the 1980s, Gero started an intense collaboration with Michel Maurette in France on the study of micrometeorites from Greenland and Antarctica, which led to many well-referenced publications. In the late 1980s, he began a long-term cooperation with the Vernadsky Institute in Moscow, which lasted until his death. Together with M. Nazarov and co-workers, mineralogical studies of different meteorites ranging from carbonaceous chondrites to lunar meteorites were made. Throughout all these decades, Gero extensively used the ion microprobes in Mainz, Nancy, and St. Louis for the study of micrometeorites and meteorite minerals and inclusions. During this time, Gero’s broad scientific interest was manifest in a variety of very different activities. He was simultaneously working on at least four very different topics, namely the origin and formation of meteorites and their components, the petrology and geochemistry of lunar rocks, the petrology and geochemistry of the upper mantle rocks, and the structure, composition, and mineralogy of micrometeorites from Antarctica and Greenland. In the mid-1990s, Gero began collaboration with Argentinean research institutions to investigate meteorites from Argentina. In the course of these activities, he identified the unusual and now famous D’Orbigny meteorite as an angrite. From 1999, he was also active with the ESA “STONE” experiments, in which satellite heat shields contained mineralogical samples to create the very first “artificial meteorite” experiments in space. Over the years, Gero’s scientific ideas shifted away from what he called mainstream thinking, in part stimulated by recent studies of tiny glass inclusions in various types of meteorites, a project he did in cooperation with Maria-Eugenia Varela from ICATE, San Juan, Argentina. For Gero, nebular condensation was the predominant process for making meteorites and their components. However, his unconventional models for the formation of glass inclusions, of eucrites and also of iron meteorites found little acceptance in the community, which does not necessarily invalidate them. Only time will tell. Recently, age and formation history of iron meteorites have indeed undergone major changes, away from conventional models. Other authors now question the cogenetic origin of chondrule minerals and glasses. After his retirement, Gero continued his scientific work in his new private office near his home, where he went to work almost every day. He discussed science and a broad range of general topics with visitors. Like in the old days at the museum, he used to take them out to nearby traditional Viennese restaurants for simple delights such as a goulash or a Wiener Schnitzel, or more sophisticated specialties, such as liver, lung, brain, or tripe. For years, Gero was a member of many scientific societies, and also received a number of recognitions and awards, of which just a few are listed here. From 1979 to 1982, he was president of the Austrian Mineralogical Society. In 1979, he received the “Grand Decoration of Honour in Silver for Services to the Republic of Austria.” In 1989, he was named adjunct professor at the University of Vienna—the same year that the Meteoritical Society meeting was held in Vienna, with Gero’s active support as a co-organizer. In 1992, Gero was named honorary member of the Russian Mineralogical Society, and he was elected to the Austrian Academy of Sciences as a corresponding member in 1993 and as a full member in 1995. In 1999, he received the Gustav von Tschermak-Seysenegg-Award of the Austrian Academy of Sciences, for his research on the petrology of the Earth’s mantle. In 2002, the asteroid 6079 was named “Gerokurat” in his honor. In 2003, he was elected an honorary fellow of the Austrian Mineralogical Society. With Gero Kurat, the society lost not only a dedicated scientist who served it in many different functions (e.g., as president), but also one of their best petrographers, and an unusually active and devoted scientist with a warm and pleasant personality, who was always ready for a joke and a good glass of wine. Nobody who was there will forget a visit to Gero’s office at the Natural History Museum, complete with a glass of wine or schnaps, under the watchful eyes of a huge portrait of Emperor Franz Josef. Besides his scientific activities, Gero had a keen interest in literature, music, and the arts. Regularly, he used to go to concerts and theater performances. In his younger years, he was an excellent tennis player. Gero will be missed by his many friends from all around the world—which he left far too soon.