photo credit


Laurel Wilkening (1944-2019)

June 18, 2019

Prof. Laurel Wilkening, a meteoriticist, university administrator, and advocate for planetary science and for women’s issues, passed away on June 4, 2019, in Tucson, Arizona, at the age of 74. Born in Richland, Washington, on Nov. 23, 1944, she grew up in Socorro, New Mexico, and got her Bachelor’s degree in Chemistry from Reed College.

It was as an undergraduate that Laurel became interested in Cosmochemistry. She received her PhD from the University of California San Diego in 1970, working with Hans Seuss. In an oral history, she described having recruited two Nobel laureates for her thesis committee, only to have one (Hannes Alfvén) say he would veto her PhD thesis if she left one portion of it in, while the other (Harold Urey) said he would veto it if she took it out. After several days of negotiations, the thesis was approved as written.

Wilkening began her scientific career studying the first samples returned from the Moon, and compared the exposure record of lunar samples, particularly as revealed by damage tracks from cosmic rays, with that of meteoritic regolith breccias. Later, her interests turned to comets. She edited the 1982 University of Arizona Press volume Comets, and was deeply involved with planning of a U.S. mission to Halley’s Comet that never materialized.

After her graduation, she worked and studied at several institutions, including the Tata Institute of Fundamental Research in Mumbai, the Max Planck Institute for Cosmochemistry in Mainz, and the Muséum National d'Histoire Naturelle in Paris.

Laurel became a faculty member at the University of Arizona in 1973 in the newly-formed Department of Planetary Sciences. In 1981, she became Head of the department and Director of the associated Lunar and Planetary Laboratory. Shortly thereafter, she became the Acting Dean of Sciences at the university when that position was created, and then Vice President for Research. From the beginning of her career at Arizona, she was instrumental in advocating for women’s issues, including pay equity, and was a key figure in the establishment of what is now the Department of Gender and Women’s Studies.

In 1988, she became Provost of the University of Washington, the first female to hold that position. In 1993, she became Chancellor of the University of California Irvine, a post from which she retired in 1998.

Throughout her career, Wilkening was a nationally prominent member of the planetary science community. She served as Vice Chair of the Advisory Committee on the Future of the U.S. Space Programs, Chair of the Space Policy Advisory Board, and Vice Chair of the National Commission on Space during the presidencies of Ronald Reagan and George H. W. Bush. Later, she became a member of the Board of Directors of The Planetary Society, serving four years as Vice President of the society.

Asteroid 75562 is named Wilkening in her honor. She was elected a Fellow of the Meteoritical Society in 1978.

Laurel was preceded in death by her husband, planetary scientist Godfrey Sill, and is survived by her brother and sister-in-law Wes and Mary Wilkening, niece Whitney Wilkening and nephew Ron Douglas.

Prof. Timothy D. Swindle

Director, Lunar & Planetary Laboratory
University of Arizona


NASA oral history:

LA Times obituary: obituary:

Category: In Memoriam

Keizo Yanai (1941-2018)

May 29, 2019

Keizo Yanai at his museum in 2010. Image Credit: Asahi Shimbun

Keizo Yanai (1941-2018)

Prof. Keizo Yanai, a founder of Antarctic meteorite research, passed away on December 17, 2018, at the age of 77, in Morioka City, Iwate Prefecture, Japan, after several years of declining health. Keizo served many years as a curator at the National Institute of Polar Research (NIPR) of Japan where he collected and allocated thousands of Antarctic meteorites for our community. He was born on July 25, 1941, in Furudono, Fukushima, Japan. He received his B.S. from Akita University and his Ph.D. degree in petrology (Mesozoic igneous rocks) from Tohoku University.

Keizo first joined a Japanese Antarctic Research Expedition (JARE) as a field geologist in 1967-68 (JARE 9) to traverse to the South Pole from Syowa Station by snow vehicles (5182 km for a round-trip). The historical traverse taught him how to operate with snow vehicles in Antarctica. He visited the Yamato Mountains in 1973-74 (JARE 15), where an original purpose of the visit was geological fieldwork in the mountains. After the incidental discovery of meteorites on the bare ice field of the Yamato Mountains in 1969 by JARE 10, the ice field was recognized to yield meteorites. During the traverse to the Yamato Mountains, Keizo found some meteorites from his vehicle and modified his plan to organize a meteorite search instead of the originally planned geologic work. In spite of many logistical challenges posed by the snow vehicles, he collected 663 Yamato-74 meteorites during the 15-days’ field work. This work established that the Antarctic ice is an excellent host of various types of meteorites. Keizo also proposed a mechanism of meteorite concentration on the ice field associated with ice sheet movement around the mountains. His model is consistent with the occurrence of various types of meteorites with different ages at the same ice field. His research showed that new meteorites would appear from the ice with time.

After the successful meteorite recovery by JARE 15, the US-Japan Joint Program for meteorite search had started around the Transantarctic Mountains. In contrast to Japanese meteorite searches using snow vehicles, the US team used helicopter and foot searches for the field work. Nevertheless, Keizo had good eyes for the first discovery of a meteorite in Victoria Land at Mount Baldr on December 15, 1976. On the same expedition, he helped find large meteorites (total ~460 kg) at Allan Hills. Next year, he went back to Allan Hills to help collect 310 ALH-77 meteorites, including ALH 77005, the first martian meteorite to be found in Antarctica. The discovery of abundant meteorites in icefields along the Transantarctic Mountains led to the creation of the Antarctic Search for Meteorites (ANSMET) program in the U.S. After completing two field seasons at Victoria Land, Keizo returned to Yamato Mountains in 1979 for meteorite hunting with a big party (JARE 20). He conducted a systematic search and collected more than 3,500 Yamato-79 meteorites and 5 meteorites around the Belgica Mountains. They include lunar and martian meteorites, which opened a new window on planetary science and into understanding our solar system.

In addition to the meteorite searches, Keizo worked hard as a curator of Antarctic meteorites at NIPR. With very limited staff, he oversaw the preparation of thin sections, and chemical analysis of the new meteorites for classification. The initial petrological and chemical data were presented with beautiful photos, which were published as the red-covered book series “Photographic Catalog of the Antarctic Meteorites”. He also hosted the annual symposium on Antarctic meteorites at NIPR, and became an editor of the Proceedings of NIPR for Antarctic Meteorites.

            Keizo desired to return to East Antarctica after the meteorite search in Victoria Land for ANSMET (1986-87), exploring a new field for meteorite hunting. The Sør Rondane Mountains are located about 600 km westward from the Yamato Mountains. A vast unknown ice field called Nansenisen was considered as a good place to find meteorites. In 1987, as a leader of the meteorite search party in JARE 29, he visited the Asuka Station which is located at the northern side of the Sør Rondane Mountains. It was hard to reach Nansenisen from the camp by snow vehicles, taking about one month for the traverse. Nevertheless, Keizo’s hunch proved to be correct, and the expedition found about 350 Asuka-87 and 2,000 Asuka-88 meteorites. After finishing the meteorite search, he accidentally wandered into a hidden crevasse area on the way to the Asuka Station from Nansenisen. On Friday, January 13th, 1989, Keizo and his colleague dropped down about 30 meters with their snow vehicle into a crevasse. To make matters worse, another colleague plunged into another crevasse during the rescue operation. Even though Keizo was injured, he encouraged the two injured colleagues to go home alive. After a week, they were rescued by a helicopter together with their meteorite collection. The accident in the Sør Rondane Mountains abruptly ended Keizo’s last expedition in Antarctica.

After the accident at the Sør Rondane Mountains, Keizo made every effort to get the two injured colleagues admitted to hospital for surgery in Japan as soon as possible against the decision of the headquarters of JARE. He deeply felt the responsibilities for his colleagues and their families. He said, “Of course, meteorite is most important, however, we have important things more than that. It may be more difficult to get the things understood by researchers than finding meteorites in Antarctica”. Finally, the operations were done in Japan. However, he was disciplined for his actions in the Sør Rondane Mountains, making it unpleasant for him to stay at NIPR. Keizo left NIPR to move to Iwate University in 1995, where he worked as a professor until his retirement in 2007. He travelled to the Mongolian desert for meteorite searches in 2002-05. He opened a private museum for meteorites and rocks in his home. After his retirement, he continued his passion for meteorite research and taught the importance of meteorites to high school students in the museum.

Keizo visited Antarctica 7 times and spent about 58 months (~ 5 years) there totally. He loved meteorites. He received many awards including Prime Minister’s Award of Japan (1969), Antarctic Service Medal from U.S. (1979) and Fellow of the Meteoritical Society (1990). His name is immortalized in the sky as the asteroid 9206 Yanaikeizo. He is survived by his wife, Yoko, and two sons, Kazuhiro and Akihiko.

Hiroshi Naraoka

Kyushu University

Category: In Memoriam

Pellas-Ryder Award for 2019 to Simon Lock

May 08, 2019

Pellas-Ryder Award for 2019 to Simon J. Lock

Simon J. Lock, currently a postdoc at the California Institute of Technology, is awarded the 2019 Pellas-Ryder Award for his paper titled “The Origin of the Moon within a Terrestrial Synestia” published in the Journal of Geophysical Research Planets in 2018. Simon Lock was a Ph.D student at the Department of Earth and Planetary Sciences, Harvard University, working with Sarah T. Stewart (now at UC Davis), when the paper was submitted. The paper makes a transformative contribution toward understanding the origin of the Earth and Moon. The study modeled the Moon forming within a new type of astronomical object, called a synestia. In the aftermath of a high-energy, high-angular-momentum Giant Impact the vaporized Earth-Impactor body forms a rapidly spinning donut-shaped object that is the synestia. Formation within a terrestrial synestia can explain the Moon’s unusual chemical relationship and isotopic similarity with the Earth. Simon presents the new theory and discusses how the thermodynamics and chemistry of molten silicates within the cooling synestia produced the volatile element depletion but retained the isotopic similarity observed in the Moon. His results will undoubtedly help meteoriticists and planetary scientists better understand the origin of the Earth-Moon system.

The Pellas-Ryder award is jointly sponsored by The Meteoritical Society and the Planetary Geology Division of the Geological Society of America.

Category: People

The Gordon A. McKay and Wiley Awards for 2018

September 26, 2018

The Gordon A. McKay Awards

Timothy Gregory Timothy Gregory

The McKay Award honors the memory of Gordon A. McKay and is supported by the McKay Fund, established in 2008 as a part of The Meteoritical Society's endowment. The award is given each year to the student who gives the best oral presentation at the Annual Meeting of The Society. The McKay Award for the 81st Annual Meeting in Moscow is given to Timothy Gregory (University of Bristol) for the presentation " Using refractory forsterite grains to test models of 26Al/27Al heterogeniety".

The Wiley Awards

Sponsored by the publisher of Meteoritics and Planetary Science, five Wiley Awards are given for outstanding oral presentations by students at the Annual Meeting. For this year's meeting in Moscow the awardees are:

Jan Hellman (Universität Münster) for the presentation "Thermal and impact history of ordinary chondrite parent bodies inferred from Hf-W chronometry".

Jane L. MacArthur (University of Leicester) for the presentation "Constraining the thermal history of Martian breccia Northwest Africa 8114".

Doreen Schmidt (Friedrich-Schiller-Universität) for the presentation " Laser simulated hypervelocity micrometeoroid impacts: orientation dependent shock effects in enstatite single crystals".

Malgorzata Sliz (University of Bern) for the presentation "Terrestrial ages of meteorites using in situ 14C and 10Be measurements".

Brendan Haas (Washington University, St. Louis) for the presentation "FIB-TEM study of 6 submicron craters from Stardust foil C2113N-A".

Category: Uncategorized

Pellas-Ryder Award for 2018 to Emily Worsham

June 26, 2018

Emily Worsham, currently a postdoc at the University of Muenster, is awarded the 2018 Pellas-Ryder award for her paper titled "Characterizing cosmochemical materials with genetic affinities to the Earth: Genetic and chronological diversity within the IAB iron meteorite complex," published in the Earth and Planetary Science Letters in 2017. Emily Worsham was a Ph.D. student in the Department of Geology, University of Maryland at the time the paper was submitted. In this paper, Worsham combined the use of very high precision isotopic measurements of three elements (Os, W and Mo) to characterize and subdivide the second largest grouping of iron meteorites, the IAB complex. These are incredibly painstaking measurements, and the study showed that some of the different subgroups formed at largely different times, and in some cases on different parent bodies. This is the first application of all three isotopic tracers to characterize the formational history of the second largest grouping of iron meteorites, and it has important implications for understanding asteroids and their relationship to Earth's own evolution.

The Pellas-Ryder award is jointly sponsored by The Meteoritical Society and the Planetary Geology Division of the Geological Society of America.

Category: Uncategorized

Friedrich Begemann (1927-2018)

May 18, 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

Category: In Memoriam

Christine Floss (1961-2018)

April 21, 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.

—Brad Jolliff, Maitrayee Bose and Pierre Haenecour 


Image Credit: Joe Angeles/WUSTL Photos

Image Credit: Joe Angeles/WUSTL Photos


Category: In Memoriam

Ursula Marvin (1921-2018)

February 21, 2018


Category: In Memoriam

Robert N. Clayton (1930-2017)

January 01, 2018


Category: In Memoriam

Elmar K. Jessberger (1943-2017)

November 30, 2017


Category: In Memoriam