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

In this interview, John Wasson (Fig.  1 ) 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.

Figure 1 Open in figure viewer PowerPoint John T. Wasson.

DS

John, thank you for letting me document your oral history. Let us start with my normal opening question, how did you get interested in meteorites?

JW

My Ph.D. research was in nuclear chemistry at MIT. Until late in my studies I thought I could be a nuclear chemist using the classical scientific method. That is, you gather data on a topic that seems interesting, you look for patterns in the data, and you write an interpretative paper that explains the data. I had learned, though, by going to Gordon Conferences, that this was not the way nuclear chemistry was being done. Nuclear chemists measured gamma ray energies as accurately as they could, they tried to fit these into energy levels diagrams, and then the nuclear physicists took over and interpreted the data. The nuclear physicists looked for the patterns in the energy‐level diagrams and made the models. That was not what I had in mind. But while I was at MIT, I heard lectures by Harold Urey, Hans Suess, and James Arnold. These were people whose backgrounds were not that different from mine and all three extolled the virtues of working on meteorites, and how you could learn neat things about how the solar system worked. That's a strength of MIT, exposure to neat ideas, and I credit the institution for doing this. So that was it. I was hooked.

DS

You have talked to us about how you became interested in meteorites, let's go back and talk about your precollege years.

     

Mt John extinction results 1988–1993

We summarize Mt John extinction measures over the past five years and show the considerable effect of recent volcanic activity on atmospheric clarity.     

The Mt John 1 metre telescope project

The Dall-Kirkham 1 m Cassegrain reflecting telescope to be installed at Mt. John University Observatory is described.Paper presented at the IAU Third Asian-Pacific Regional Meeting, held in Kyoto, Japan, between 30 September–6 October, 1984.     

John S. Lewis,Worlds without End

Earth, Moon, and Planets -     

The Hercules Échelle Spectrograph at Mt. John

The High Efficiency and Resolution Canterbury University Large échelle Spectrograph (HERCULES) a fibre-fed échelle spectrograph that was designed and built at the University of Canterbury and has been in operation at Mt. John University Observatory since April 2001.HERCULES receives light from the f/13.5 Cassegrain focus of the 1 m McLellan telescope. Resolving powers of R = 41 000, 70 000 and 82 000 are available. An R2 200 × 400 mm échelle grating provides dispersion and cross-dispersion uses a large BK7 prism in double pass. The wavelength coverage is designed to be 380–880 nm in a single exposure. The maximum detective quantum efficiency of the fibre, spectrograph and detector system is about 18% in 2 arc second seeing. High wavelength stability (to better than 10 ms^-1 in radial velocity) is achieved by installing the whole instrument in a large vacuum tank at 2–4 torr and by there being no moving parts. The tank is in a thermally isolated and insulated environment. The paper describes the design philosophy of HERCULES and its performance during the first year of operation. Now deceased; formerly at This revised version was published online in July 2006 with corrections to the Cover Date.     

John S. Lewis,Rain of Iron and Ice

Earth, Moon, and Planets -