Dr. Frank A. Podosek, researcher in geochemistry, cosmochemistry and meteoritics, passed away at the age of 83 on June 8, 2025.
Frank was born in Ludlow, Massachusetts on November 26, 1941. He attended Harvard College, graduating in 1964 with a A.B. degree in Physics. While having many choices as to where he could pursue graduate work as an experimentalist, he chose the University of California, Berkeley, because (as he would later relate) the noble gas mass spectrometrist John H. Reynolds, his soon-to-be advisor, showed him how you could put a piece of a meteorite in a vacuum oven, then heat it, analyze the noble gases it evolved, and tell from ink on a strip chart on the other side of the room how old the solar system was. This was Frank’s introduction into meteoritics and cosmochemistry.
While in Berkeley, Frank did research into Iodine 129 - Xenon 129 relative age dating of chondrites as well as into the abundance of the extinct radionuclide Pu 244 in the early Solar System. In 1969, Frank was awarded the Ph.D. in Physics from Berkeley. From there he joined the “Lunatic Asylum” of G. J. Wasserburg at Caltech, where his work until 1973 included investigation of surface-correlated noble gases from the solar wind in lunar soils, further work in I-Xe dating of meteorites, and cosmic ray exposure ages of meteorites and lunar rocks by noble gas mass spectrometry. During this time he also conducted several Ar 40-Ar 39 dating studies of lunar rocks. In this regard, it is noteworthy that this latter kind of study was performed by him at this time on two nakhlite achondrite meteorites (Lafayette and Nakhla), establishing a gas-retention age of only 1.3 Gy for them, which would later be taken as partial evidence that they and other SNC meteorites originated from impacts on the planet Mars.
In 1973 Frank was hired as an Assistant Professor in the Earth and Planetary Sciences Department at Washington University in Saint Louis, under the considerable desire of Robert M. Walker to create a vibrant and modern planetary research team at the University. At the same time, Raymond Arvidson, Ghislaine Crozaz and G. J. Taylor were also hired in that Department.
For the next several years Frank conducted numerous noble gas studies on lunar rocks and meteorites along with colleagues at Washington University. In 1977 he made his first venture into the study of terrestrial noble gases and their possible use in investigating the degassing history of the Earth. This study attracted the notable attention of Professor Minoru Ozima of the University of Tokyo, and thereafter, becoming close friends, they published many joint papers on noble gases in terrestrial and extraterrestrial materials. During this time and into the early 1980’s, Frank explored in several diverse studies the so-called “Missing Xe” problem involving the Earth’s apparent deficiency in elemental Xe compared to meteorites. In 1983 he and Ozima published the book Noble Gas Geochemistry, describing the state of the art at the time.
Also in the early 1980’s, now as Full Professor, Frank’s attention turned to solid source mass spectrometry, with his establishment of laboratories in the Physics Department and later the Earth and Planetary Sciences Department. Along with his wife, geochemist Dr. Joyce Brannon, he investigated Rb-Sr and initial Sr composition studies of various terrestrial ore deposits, while pursuing into the 1990’s a wide variety of cosmochemical studies with students and colleagues, among them of refractory inclusions in meteorites, the s-process Ba isotopic composition in presolar SiC grains, Nd isotopic studies of ancient terrestrial rocks, actinide abundances in meteorites, and the double beta decay of Te isotopes, establishing the longest half-life ever measured. In this same interval Frank participated in multiple committees and review panels for NASA and the Meteoritical Society, and authored many authoritative papers and review articles on cosmochemisty.
In 2000, Frank assumed the chief editorship of Geochimica et Cosmochimica Acta, a position that he held until his retirement from academia in 2011, significantly enhancing the journal's impact, and earning him the 2009 Geochemical Society Distinguished Service Award for service that "greatly exceeds the normal expectations of voluntary service." Despite this heavy editorial burden, Frank continued to pursue terrestrial and extraterrestrial isotopic studies into noble gases, s-process Sr, and Ba isotopic anomalies in Orgueil. Eventually, the press of editiorship duties suppressed Frank’s scientific output, but not his mentorship of students nor his mastery of a vast range of investigations into terrestrial and extraterrrestrial geochemistry.
During the time he was a professor at Washington University, Frank taught numerous courses in geophysics, geochemistry and absolute age dating. His problem sets were original, complex and difficult, both instructive and legendary. Successfully solving them entitled one to bragging rights as well as considerable physical insight. As a teacher, his strength was not in the style, but rather in the substance of what he said. He was a master analyst, and his massive intellect burned subtly under his humble demeanor. Frank had immense personal integrity as well as intellectual and personal generosity. It is fitting that he passed away peacefully from heart failure during a rest period after playing cards with his son Steve, because his love of games and puzzle solving was a passion to which he devoted much of his life after retirement. He is survived by his daughter Elaine, and two of Steve’s children.
Submitted by Thomas J. Bernatowicz