Leonard Medal Research Articles

Leonard Medal Citation for Monica Grady

Leonard Medal Citation for Monica Grady

Michael Ewing Zolensky as the 55th recipient of Leonard Medal

Michael Ewing Zolensky as the 55th recipient of Leonard Medal

Citation for Dr. Katharina Lodders, Leonard Medalist, 2021

AbstractThe 2021 Leonard Medal was awarded to Dr. Katharina Lodders, in person, at the 2021 Annual Meeting of the Meteoritical Society in Chicago, IL, USA. This is the citation presented for Dr. Lodders.

Leonard Medal for Andrew M. Davis

Leonard Medal for Andrew M. Davis

Edward R. D. Scott (1947–2021): A tribute to an exceptional scientist and wonderful man

Edward R. D. Scott (1947–2021): A tribute to an exceptional scientist and wonderful man

Leonard Medal Acceptance

Leonard Medal Acceptance

Acceptance of the Leonard Medal of the Meteoritical Society, 2019

I would like to thank Sasha for the kind words, all those who took the time and effort to write letters nominating me for the Leonard Medal, and the Leonard Medal Committee of the Meteoritical Society for awarding me this great honor. Many of the past recipients of this award have been scientific heroes to me, and it is hard to express how it feels to be included in this distinguished group. I was born as the first son in a family that farmed mandarin oranges. I loved to play in the orange farm to find small fragments of rock crystals and to be lost in thought. At that time, I dreamed of becoming a scientist. According to the traditional Japanese custom, the first son must succeed the family business, but my parents encouraged everything that I wanted to do. This was probably due to their experiences when they were young, because some of their dreams might not be realized due to Japanese social and economic situations in those days. Thank you, Mom and Dad. I wish that they were still with us so that they could see the results of their encouragements. I was a student of Shigeho Sueno and Naoki Onuma at the University of Tsukuba. Mineo Kumazawa encouraged me all the time. The University of Tsukuba was just being constructed in the wild when I entered. I learned frontier spirit from the university. I have learned an open-minded policy of laboratory management from Shige Sueno and exploration strategy for research from Naoki Onuma and Mineo Kumazawa. They generously gave me access to a new state-of-the-art secondary ion mass spectrometer when I entered my master's course. I used to play with the SIMS like playing with my pet. I changed hardware and software of the SIMS every day through my whole graduate student life. After my PhD, I was fortunate to be employed at the same university. This was the time when I started to study meteorites. Jim Papike came to my university and invited me to South Dakota, United States, for 1 year and I worked with Chip Shearer. I have learned American research style as well as American culture from them, although South Dakota might be unique in America. I then moved to Tokyo Tech in 1994. The life of Tokyo Tech was very stimulating for me because many crazy colleagues worked on the same floor of my building, such as Kiyoshi Nakazawa, Shige Maruyama, and Eiichi Takahashi. The floor was a place where new ideas and new motivation were born. The ideas were discussed in a joint seminar with Hiroshi Nagasawa. I went to Gakushuin University weekly with my students for the seminar. In parallel, I struggled with a dilemma why my science style might be a little bit different from others. John Wasson helped me to integrate my style with others, especially with John's style, and vice versa. Collaboration with Sasha Krot started from this time. I finally moved to Hokkaido University in 2005. I opened the Isotope Imaging Laboratory, which is now an international open facility and many colleagues come to use SIMS from all over the world. This is so gratifying and I appreciate that I have learned so much from my teachers, colleagues, postdocs, and students. On a personal note, my family has been very supportive through my crazy scientific life. I thank my wife, Atsuko, and two sons, Naoki and Terumi. Atsuko helped me to recognize the important things in family and relationships. She also has encouraged me to keep fit and healthy, even as I resisted. To end, I thank all of you for providing a vibrant and enjoyable research community, which I am very proud to be a part of.

2019 Leonard Medal to Hisayoshi Yurimoto

2019 Leonard Medal to Hisayoshi Yurimoto

The discovery of chemically produced mass independent isotope effects: The physical chemistry basis and applications to the early solar system, planetary atmospheres, and the origin of life

The discovery of chemically produced mass independent isotope effects: The physical chemistry basis and applications to the early solar system, planetary atmospheres, and the origin of life

2016 Leonard Medal for Hiroko Nagahara

2016 Leonard Medal for Hiroko Nagahara

Tektites, Apollo, the Crust, and Planets: A Life with Trace Elements

Stuart Ross Taylor, MSc (University of New Zealand), PhD (Indiana University), ScD (University of Oxford), FAA, AC, always called Ross, grew up on a farm near Ashburton, New Zealand. Ross has worked on a wide variety of topics in trace element geochemistry, including the composition and evolution of the Moon, the continental crust, tektites, impact glasses, and island arc rocks. In 1969 he carried out the first chemical analysis of the first returned lunar sample at NASA in Houston. He has published 10 books and 240 papers in scientific journals. He was awarded the V.M. Goldschmidt Award of the Geochemical Society in 1993. In 1994 he was elected a Foreign Associate of the National Academy of Sciences. In 1998, he was awarded the Leonard Medal of the Meteoritical Society, in 2002 the Bucher Medal of the American Geophysical Union, and in 2012 the Shoemaker Distinguished Lunar Scientist Medal of the NASA Lunar Science Institute. Asteroid 5670 is named Rosstaylor.

Heinrich Wänke (1928–2015)

Heinrich Wänke (1928–2015)

2015 Leonard Medal for Jeff Cuzzi

2015 Leonard Medal for Jeff Cuzzi

2014 Leonard Medal for Roger H. Hewins

2014 Leonard Medal for Roger H. Hewins

Oral histories in meteoritics and planetary science – XXII: John T. Wasson

AbstractIn this interview, John Wasson (Fig. ) describes his childhood and undergraduate years in Arkansas and his desire to pursue nuclear chemistry as a graduate student at MIT. Upon graduation, John spent time in Munich (Technische Hochschule), the Air Force Labs in Cambridge, MA, and a sabbatical at the University of Bern where he developed his interests in meteorites. Upon obtaining his faculty position at UCLA, John established a neutron activation laboratory and began a long series of projects on the bulk compositions of iron meteorites and chondrites. He developed the chemical classification scheme for iron meteorites, gathered a huge set of iron meteorite compositional data with resultant insights into their formation, and documented the refractory and moderately volatile element trends that characterize the chondrites and chondrules. He also spent several years studying field relations and compositions of layered tektites from Southeast Asia, proposing an origin by radiant heating from a mega‐Tunguska explosion. Recently, John has explored oxygen isotope patterns in meteorites and their constituents believing the oxygen isotope results to be some of the most important discoveries in cosmochemistry. John also describes the role of postdoctoral colleagues and their important work, his efforts in the reorganization and modernization of the Meteoritical Society, his contributions in reshaping the journal Meteoritics, and how, with UCLA colleagues, he organized two meetings of the society. John Wasson earned the Leonard Medal of the Meteoritical Society in 1992 and the J. Lawrence Smith Medal of the National Academy in 2003.John T. Wasson.image

Oral Histories in Meteoritics and Planetary Science-XXI: Donald Burnett

In this interview, Donald Burnett (Fig. 1) describes how he applied to the University of Chicago, with considerable support from his father, where he took classes from Harold Urey and was inspired by Ed Anders to pursue a career in nuclear chemistry and, later, cosmochemistry. As a graduate student at the University of California at Berkeley, Don learned to use charged-particle tracks as a detector for radioactive nuclei, a technique that he applied to a wide variety of problems over the next 20 years, including the neutron profile probe that was deployed on the Moon. After a one-year postdoc with William Fowler at the California Institute of Technology, he became involved with Jerry Wasserburg, who ultimately obtained a faculty position for him in the Geology Division. Since then, Don has worked on a number of fundamental problems in cosmochemistry, chronology of the solar system, the initial Pu/U abundance, fractionation of U and Pu in igneous processes, and elemental abundances. This last interest led him to advocate, propose, and lead the Genesis space mission to collect and return samples of the solar wind. The crash of the return capsule caused alarm, but some aspects of the mission were unaffected and others have been successfully handled, so that several major new results have been published: the lack of an SEP component in lunar samples, the Ne and Ar composition of the solar wind, and, most importantly, the oxygen and nitrogen isotopic composition of the Sun. Don received the Leonard Medal in 2012.

Oral Histories in Meteoritics and Planetary Science—XIX: Klaus Keil

Abstract– Klaus Keil (Fig. 1) grew up in Jena and became interested in meteorites as a student of Fritz Heide. His research for his Dr. rer. nat. became known to Hans Suess who––with some difficulty––arranged for him to move to La Jolla, via Mainz, 6 months before the borders of East Germany were closed. In La Jolla, Klaus became familiar with the electron microprobe, which has remained a central tool in his research and, with Kurt Fredriksson, he confirmed the existence of Urey and Craig’s chemical H and L chondrite groups, and added a third group, the LL chondrites. Klaus then moved to NASA Ames where he established a microprobe laboratory, published his definitive paper on enstatite chondrites, and led in the development of the Si(Li) detector and the EDS method of analysis. After 5 years at Ames, Klaus became director of the Institute of Meteoritics at the University of New Mexico where he built up one of the leading meteorite research groups while working on a wide variety of projects, including chondrite groups, chondrules, differentiated meteorites, lunar samples, and Hawai’ian basalts. The basalt studies led to a love of Hawai’i and a move to the University of Hawai’i in 1990, where he has continued a wide variety of meteorite projects, notably the role of volcanism on asteroids. Klaus Keil has received honorary doctorates from Friedrich‐Schiller University, Jena, and the University of New Mexico, Albuquerque. He was President of the Meteoritical Society in 1969–1970 and was awarded the Leonard Medal in 1988. Klaus Keil at the University of Hawai’i at Manoa, 2007.image

Oral Histories in Meteoritics and Planetary Science – XVII: Joseph Goldstein

Abstract– In this interview, Joseph Goldstein (Fig. 1) recounts how he became interested in meteorites during his graduate studies working with Robert Ogilvie at MIT. By matching the Ni profiles observed across taenite fields in the Widmanstätten structure of iron meteorites with profiles he computed numerically he was able to determine cooling rates as the meteorites cooled through 650–400 °C. Upon graduating, he worked with a team of meteorite researchers led by Lou Walter at Goddard Space Flight Center where for 4 years he attempted to understand metallographic structures by reproducing them in the laboratory. Preferring an academic environment, Joe accepted a faculty position in the rapidly expanding metallurgy department at Lehigh University where he was responsible for their new electron microprobe. He soon became involved in studying the metal from lunar soils and identifying the metallic component from its characteristic iron and nickel compositions. Over the next two decades he refined these studies of Ni diffusion in iron meteorites, particularly the effect of phosphorus in the process, which resulted in superior Fe‐Ni‐P phase diagrams and improved cooling rates for the iron meteorites. After a period as vice president for research at Lehigh, in 1993 he moved to the University of Massachusetts to serve as dean of engineering, but during these administrative appointments Joe produced a steady stream of scientific results. Joe has served as Councilor, Treasurer, Vice President, and President of the Meteoritical Society. He received the Leonard Medal in 2005, the Sorby Award in 1999, and the Dumcumb Award for in 2008. Joseph Goldstein.image

Oral Histories in Meteoritics and Planetary Science - XV: John Wood

Abstract– John Wood (Fig. 1) was trained in Geology at Virginia Tech and M.I.T. To fulfill a minor subject requirement at M.I.T., he studied astronomy at Harvard, taking courses with Fred Whipple and others. Disappointed at how little was known in the 1950s about the origin of the earth, he seized an opportunity to study a set of thin sections of stony meteorites, on the understanding that these might shed light on the topic. This study became his Ph.D. thesis. He recognized that chondrites form a metamorphic sequence, and that idea proved surprisingly hard to sell. After brief service in the Army and a year at Cambridge University, John served for 3 years as a research associate with Ed Anders at the University of Chicago. He then returned to the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, where he spent the remainder of his career. At Chicago, he investigated the formation of the Widmanstatten structure, and found that the process informs us of the cooling rates of iron meteorites. Back in Cambridge, he collaborated with W. R. Van Schmus on a chondrite classification that incorporates metamorphic grade, and published on metal grains in chondrites, before becoming absorbed by preparations for the return of lunar samples by the Apollo astronauts. His group’s work on Apollo samples helped to establish the character of the lunar crust, and the need for a magma ocean to form it. Wood served as President of the Meteoritical Society in 1971–72 and received the Leonard Medal in 1978. Figure 1. John Wood. Download figure to PowerPoint

Oral Histories in Meteoritics and Planetary Science––XVI: Grenville Turner

Abstract– In this interview, Grenville Turner (Fig. 1) recounts how he became interested in meteorites during postdoctoral research with John Reynolds at the University of California, Berkeley, after completing a DPhil with Ken Mayne at the University of Oxford. At Berkeley, he worked on xenon isotopes with fellow students Bob Pepin and Craig Merrihue, but Reynolds’ insistence that they analyze all the inert gases in their samples meant that they also made important contributions to Ne isotope studies and potassium‐argon dating leading to the Ar‐Ar technique. In 1964, Grenville obtained a teaching position at the University of Sheffield where he developed his own laboratory for inert gas isotope measurements. After the return of samples from the Moon by the Apollo program, he became involved in determining the chronology of volcanism and major impacts on the Moon. In 1988, Grenville and his team moved to the University of Manchester as part of a national reorganization of earth science departments. During the post Apollo years, Grenville’s interest turned to the development of new instrumentation (resonance ionization mass spectrometry and the ion microprobe), and to problems in terrestrial isotope geochemistry, particularly the source of inert gases in fluid inclusions. He received the Leonard Medal of the Meteoritical Society in 1999, and he has also received awards from the Royal Society, the European Association of Geochemistry, and the Royal Astronomical Society. Grenville Turner.image