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In Memoriam

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Friedrich Begemann (1927-2018)

Friedrich Begemann passed away on May 11, at the age of 90. Friedrich (‘Fred’) was the director of the Isotope Cosmology Department at the Max-Planck-Institut für Chemie (MPI-C) in Mainz (Germany) from 1978 until his retirement in 1995 and the 1995 recipient of the Meteoritical Society’s Leonard Medal.

Friedrich Begemann was born in late 1927 in the small village of Almena in Westphalia, close to the border to Lower Saxony and near the river Weser. Too young to get drafted for serious military service in World War II, he took up a study of physics at the University of Göttingen in 1947 and completed his diploma thesis working with Friedrich Houtermans, who by then had returned to Göttingen after being forced to leave in 1933. When Houtermans moved to Bern, Switzerland, in 1952, Begemann followed him there (together with Johannes Geiss) to work on his PhD thesis. In his work with Houtermans Friedrich Begemann dealt with the products of the radioactive decay of U and Th into (eventually) isotopes of lead. He determined the half-life of radioactive Ra-E (210Bi), an isotope in the decay chain leading from 238U to 206Pb, and applied the Ra-D (210Pb) method suggested by Houtermans to determine a ‘chemical age for minerals’. Counting activities was a major part of this work, but even in these early days already mass spectrometric determinations of lead isotopes.

Following his Ph.D. work, Friedrich Begemann moved to Chicago to work with Willard F. Libby as a Research Associate at the Enrico Fermi Institute. Here he focused on tritium (3H), the radioactive isotope of hydrogen, and over the following decade published a number of important papers on its abundance, origin and distribution. This was a hot topic at the time due the enormous amounts of tritium released into the environment from hydrogen bomb tests. Drawn to the group of Harold Urey and the likes of (again) Johannes Geiss and Jerry Wasserburg also at Chicago, it was at this time that Friedrich Begemann got into contact with meteorites and analyses of stable noble gas isotopes, specifically 3He, the decay product of tritium. His paper with Johannes Geiss and D.C. Hess, in which they reported the first determination of a cosmic-ray exposure (CRE) age of a meteorite from combined tritium/3He analysis is a milestone. It set the stage for the development of a completely new branch in Meteoritics. The study of cosmic ray products in meteorites today is a mature field. Not only does it provide the means to determine exposure ages, thus travel times from parent body to Earth, but it also puts constraints on their pre-atmospheric size – both very basic properties.

Back to Germany in 1957, Friedrich Begemann joined Friedrich Paneth at the MPI-C in Mainz, where he remained until his retirement in 1995, interrupted only by a short stint as a Guest Professor at the University of Bern. Within a short time in Mainz he also became an adjunct professor at Johannes-Gutenberg University, teaching Experimental Physics in addition to doing research at the Max-Planck-Institute. While his early work in Mainz is still dominated by the study of radiation effects, including such in rocks brought back from the Moon by Apollo, with time he focused more on the mass spectrometric determination of stable isotope compositions, noble gases in particular, but also elements like potassium and magnesium, where he was one of the first to confirm the existence in the early Solar System of now extinct 26Al from overabundances of 26Mg in CAIs found by his good friend Jerry Wasserburg.

Having already been appointed a ‘Scientific Member’ of the Max-Planck Society in 1969, Friedrich Begemann became the director of a new Department at the MPI-C in 1978, which he led until his retirement in 1995. This allowed him to expand this direction of research. A number of important contributions from this time, to mention a few, deal with noble gases in Martian meteorites and the isotopes of noble gas and other trace elements in presolar grains. He also contributed to refined understanding of cosmic ray interactions with meteorites by pointing out the “matrix effect” and by enabling the performance of irradiation simulation experiments on artificial meteorites. For this and his earlier work he was awarded the Leonard Medal of the Meteoritical Society in 1995. He also served the Society as a councilor from 1981 to 1984 and together with Heinrich Wänke organized the 1983 Annual Meeting with an unforgettable evening tour and Dinner on the Rhine River.

Friedrich Begemann contributed strongly to making and keeping contact with friends and colleagues in the former East Bloc, in particular Russia, from where numerous guests came to visit and perform research at the Max-Planck Institute, in particular in the early 1990s after the opening of the Wall. China was also on his mind, and when the country began to open up after the end of the Cultural Revolution, he was a member of the first delegation from the Max-Planck Society visiting China to establish scientific contact. He also led the consortium study of the large Jilin meteorite, the results of which were published in EPSL in 1985 and in MAPS in 1996.

Many of us will not know that cosmochemistry was not the only scientific endeavor of Friedrich Begemann during his productive years and also after his official retirement. Rather than only the origin and history of the Universe and the Solar System, he also made important contributions in archaeometry – getting insight into the history of humankind. For this, he revisited what he had done during his diploma and doctoral theses – the decay of U and Th into lead, but now solely by precise mass spectrometric studies of lead isotopes. His work in this field, involving studies of ores and early metal artefacts from places like Troia and Lesbos, among others, contributes to our knowledge of the sources of raw metals such as tin and copper as they were used during the Bronze Age, which in turn tells us about trade patterns during this time.

A defining characteristic of Friedrich Begemann was his analytical mind and sharp wit, where he was second to none. He was able to detect the slightest flaw or uncertainty in your logic and he would tell you so. Sometimes this may have been hard to take by some of us, but we definitely need such minds!

Friedrich Begemann’s wife Margarete died slightly more than a year ago, and after that also Friedrich’s health started to deteriorate. His sharp mind, however, remained to the last day. He leaves daughter Marieluise, son Hanns-Friedrich and granddaughter Eva.

Ulrich Ott

16:09 | Obituary

In Memoriam

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Christine Floss (1961-2018)

Dr. Christine Floss died unexpectedly at her home in St. Louis on April 19, 2018, at age 56. She is deeply missed by her family, friends, and colleagues. Christine was a research professor in the Department of Physics and McDonnell Center for Space Sciences at Washington University in St. Louis. Christine was a long-time member and a fellow of the Meteoritical Society. She was an expert in the trace-element and isotopic analysis of planetary materials, meteorites, and presolar grains, studying the origin and evolution of the Solar System. She was a gifted and dedicated scientist and mentor, and an extraordinary colleague, collaborator, and friend to many in the cosmochemistry and planetary science community.

Christine’s research interests spanned a wide variety of extraterrestrial materials, from lunar samples to meteorites to presolar grains to returned samples from the NASA Stardust and Genesis missions to Antarctic micrometeorites to interplanetary dust particles. She played an important role in the chemical and isotopic studies of interplanetary dust particles, micrometeorites, and primitive chondrites to understand the origins and abundances of presolar and protosolar components in these materials. She performed isotopic and compositional studies of residues from Stardust craters and hypervelocity impact experiments to characterize the samples returned from comet 81P/Wild 2. Identification and characterization of craters from the Stardust interstellar dust collector was also part of her scientific work. She played a leading role in trace element distribution studies of individual minerals in extraterrestrial samples, to understand their petrogenesis as well as secondary effects occurring on their parent bodies (thermal metamorphism, aqueous alteration).

Christine earned a BA in German from Purdue University in 1983, a second degree in Geology from Indiana University, Bloomington in 1987, and a PhD in Geochemistry from the Department of Earth and Planetary Sciences at Washington University in St. Louis in 1991. Her dissertation focused on rare earth element distributions in meteorites (e.g., Aubrites) and ferroan anorthosites, working with Ghislaine Crozaz. She showed that the heterogeneous rare earth element patterns in oldhamite from aubrites reflect condensation from the solar nebula, rather than igneous processes in a parent body, as was believed at that time. It was during her time at Washington University that she developed her expertise with—and love of—the ion microprobe as her instrument of choice to explore the characteristics and origins of extraterrestrial materials.

Christine moved to Heidelberg, Germany, in 1991 for a research scientist position at the Max-Planck-Institut für Kernphysik. In 1993, while in Heidelberg, she married Frank Stadermann. While at the Max-Planck-Institut, she published on aubrites, angrites, pallasites, showing early-on the breadth of her interests. She was also involved with trace element studies of lunar samples (returning often to ferroan anorthosites), eucrites, lodranites, and acapulcoites.

In 1996, Christine and Frank were invited to return to Washington University to work with their former advisors, Robert Walker and Ghislaine Crozaz. Christine joined the Laboratory for Space Sciences, now a part of the McDonnell Center for the Space Sciences, as a research scientist, and through the ensuing years, worked her way to become a full research professor. Christine worked with numerous colleagues, doing careful ion microprobe work that was essential in many studies. Along with Frank Stadermann, Ernst Zinner, and other coworkers, she developed unique expertise with the first Cameca NanoSIMS 50 instrument. Christine had over 250 coauthors and over 100 publications in peer-reviewed journals, and she led numerous research projects as principal investigator. In 2006, main-belt asteroid 6689 was named asteroid Floss.

In addition to her prolific research career, Christine played an active role in the cosmochemistry community. She was a member of the ANSMET (The Antarctic Search for Meteorites) team in 2014–2015, a reflection of her adventurous spirit. She served the scientific community in many ways, as a member of the Antarctic Meteorite Working Group, CAPTEM (The Curation and Analysis Planning Team for Extraterrestrial Materials), LPSC program committee, various student and early career awards committees, the Council of the Meteoritical Society, and much service on NASA review panels. She also served as the associate editor for Meteoritics and Planetary Science from 2005–2015. All of these activities reflected Christine’s personality and character; she was selfless, serious, level headed, balanced and fair, always positive and never complaining, a consummate professional.

At Washington University, Christine had a special role. Following in the giant footsteps of the likes of Robert Walker, Ernst Zinner, and Thomas Bernatowicz, Christine took on the role of lead scientist for the NanoSIMS and Auger Electron Microprobe laboratories, and served as mentor extraordinaire to a new generation of cosmochemistry students and analysts. She was a wonderful advisor to both undergraduate and PhD students; she always took the time to support all her students whenever they needed help, whether it was work-related or personal. In 2015, she was honored with a Washington University Outstanding Faculty Mentor award. All of her graduate students received NASA Earth and Space Science Fellowships for their research, which further attests to her excellent mentoring. She carried on a great tradition of the McDonnell Center for the Space Sciences at Washington University in training and mentoring students who have become strong contributors in the field of space science and who will certainly carry on in the same spirit of scientific curiosity and excellence as she did.

Christine is survived by her parents, Heinz G. Floss and Inge Floss; three siblings, Peter (and Barbara) Floss, Helmut Floss and Hanna Floss (and Tony Andrews); three children, Alisha, Erin (and Jeff) Hillam, Ashley Heavilon, and Amanda Stadermann, and three grandchildren (Minnie, Ezra, and Ruby Hillam).

Christine, you left us too soon; you will be sorely missed but dearly remembered.

—A memorial service will be held on Wednesday, April 25, at 2 pm at the Ethical Society in St. Louis, where Christine was a long-standing member and served in multiple roles on the Board of Trustees. In lieu of flowers, donations in her honor may be made to Ethical Society of St. Louis or Friends of the Children of Haiti. Christine was heavily involved in the work of both these social groups and traveled several times to Haiti to volunteer her services to children with needs.

Brad Jolliff, Maitrayee Bose and Pierre Haenecour

Image Credit: Joe Angeles/WUSTL Photos
22:23 | Obituary

In Memoriam

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Ursula Marvin (1921-2018)

Ursula Marvin passed away on February 12, 2018, at the age of 96. More details are available here.
11:10 | Obituary

New guidelines for Gifts and Grants

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"Guidelines for Gifts and Grants" on the home page have been changed.

19:07 | News

The 2018 J. Lawrence Smith Medal

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The 2018 J. Lawrence Smith Medal awarded to Kevin McKeegan

The 2018 J. Lawrence Smith Medal of the National Academy of Sciences was awarded to Kevin D. McKeegan (University of California, Los Angeles). "The medal is awarded every three years for investigations of meteoric bodies and includes a $50,000 prize. The award was established as a gift from Sarah Julia Smith in memory of her husband and has been presented since 1888." Kevin received the 2018 medal for "For contributions to understanding of the processes and chronology of the early solar system as recorded by primitive meteorites, for innovation in analytical instrumentation, and for showing that the oxygen isotopic compositions of the Earth and rocky planets and meteorites are distinctly different from that of the Sun."  Past recipients of the medal include Hiroko Nagahara (2015), Hap McSween (2012), Bob Clayton (2009), Klaus Keil (2006) and John Wasson (2003).

18:50 | People