Oral Hist Honda.Fm

Meteoritics & Planetary Science 38, Nr 7, Supplement, A177–A187 (2003) Abstract available online at http://meteoritics.org Report Oral histories in meteoritics and planetary science: XI. Masatake Honda Ursula B. MARVIN Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts 02138, USA E-mail: [email protected] (Received 27 May 2003) Abstract–Masatake Honda majored in inorganic chemistry at the University of Tokyo and then pursued graduate studies in geochemistry. In 1943, he completed his first research project, which yielded new data on the behavior of strontium in carbonates. He then spent the next two years as a technical officer in the Japanese Imperial Navy. While on duty, he gained expertise in the important new field of ion exchange methods, which he ultimately chose as the topic for his Ph.D. thesis and then expanded into a book. In 1955, Honda traveled to Switzerland and spent a year in research laboratories at Bern and Zürich. He then joined Professor James R. Arnold at Princeton University and soon began focusing his research on cosmic-ray produced nuclides in meteorites. Two years later, he accompanied Dr. Arnold to the University of California at La Jolla where they joined the research group of Professor Harold C. Urey. Honda developed techniques for measuring terrestrial ages of meteorites and showed that most of them have survived weathering for vastly longer periods than had been anticipated. After spending nearly eight years abroad, he returned to Japan in 1962 as a full professor at the University of Tokyo. During the Apollo missions, he performed research on cosmogenic nuclides in lunar rocks, surface soils, and deep drill cores. In the same period, he studied terrestrial histories of numerous Antarctic meteorites. In 1992, he retired from his professorship but he continues to carry on his research and to publish papers. In 1987, the Meteoritical Society presented its Leonard Medal to Masatake Honda for his pioneering work in establishing the abundances and production rates of stable, long-lived, and short-lived nuclides by cosmic irradiation of meteorites and lunar samples. UBM: Masa, today we call you a cosmochemist, but that UBM: Did Prof. Minami introduce you to the study of is a Space Age term. As a young student in Japan, did you meteorites? start out by majoring in inorganic chemistry? MH: No, but he made me aware of them. Professor MH: Yes, but in 1942, when I was a senior in the Tokyo Minami always used to wear a thick hat in the geochemistry Imperial University, I decided to study geochemistry in laboratory. When anybody asked him his reason he would say graduate school. The course I took toward graduation was that someday the hat might protect him from a meteorite taught by Professor Yuji Shibata, who had introduced the field falling on his head. Of course, we all took this to be a joke. of geochemistry into Japan. Professor Shibata had studied But, we knew that in his school days in 1923, he had worked chemical coordination compounds at Zürich under Professor on the Kushiike chondrite that had fallen in 1920, the year Alfred Werner and had learned to measure rare elements by when I was born in Tokyo. Meteorite falls were rare in Japan, spectroscopic analyses from Professor Georges Urbain at Paris. and it was an especially rare opportunity for him to be able to UBM: Did you do your graduate work with Professor do reliable analytical work on a fresh fall, under the Shibata? instruction of Professor Shibata. MH: No. In graduate school, I worked under Professor UBM: So, meteorites were one of Professor Minami’s Eiiti Minami, who was an assistant professor of inorganic special interests? chemistry. Professor Shibata retired in 1962 on his 61st MH: Yes, they were. He had written a monograph on birthday. meteorites in 1930 when he was 30 years old. He also was A177 © Meteoritical Society, 2003. Printed in USA. A178 U. B. Marvin examined. I now feel that Professor Minamu was right in rejecting the subject I had proposed as a young student who had no experience at all of research in geochemistry. UBM: So, you began working on strontium? MH: Yes. I started studying the chemistry of strontium and realized very soon that Sr always occurs with Ca, and Ca is an important bioelement that forms corals and other calcareous organisms in the oceans. UBM: It seems that you had a biogeochemical problem, after all. MH: Yes, I had. I quickly learned that calcium carbonate (CaCO3) crystallizes either as hexagonal calcite or as orthorhomic aragonite, but Sr carbonate enters only the aragonite structure. Corals consist of aragonite because, for some mysterious reason, the CaCO3 from seawater always forms the aragonite structure in the presence of Mg. Therefore, Sr and Ca occur together in marine deposits such as coral. But, they do not occur together in continental carbonate rocks because Sr is ejected from the structure during their recrystallization to calcite. The Sr returns to the ocean, Fig. 1. Masatake Honda with two prints of the Brenham pallasite at eventually. This is the reason why Sr/Ca is 1 atom percent Arizona State University in 2002. higher in sea water than the terrestrial mean value of <0.1 atom percent in continental limestone. In the most extreme cases, interested in the rare earth elements and their abundances in stalactites and stalagmites contain the very least amount of Sr rocks and meteorites. In 1933, he went to Göttingen, relative to Ca to be found in any carbonates. Germany, to study rare earth patterns in the laboratory of Prof. Minami supplied me with a glass prism Professor Victor M. Goldschmidt. He stayed there until 1935 spectrometer and a spark source generator. The presence of Sr and then left for Japan, just two months before Professor in association with Ca could be observed by the naked eye Goldschmidt, himself, had to resign his job, due to the rise of because the strongest blue Sr line, at 4607 angstroms, stands antisemitism, and leave Göttingen for his home country, out easily from among the weak Ca lines nearby. The Norway. principle was the same as the one used to determine the I would like to add that Dr. Minami was a very magnitude of visible stars. This was my first scientific project. independent person with unusual interests inside and outside I worked on it for about nine months and found it to be of science. He had been an instructor in the department of unforgettable. Professor Minami and I published a paper on mineralogy at the Imperial University of Tokyo before the strontium contents in natural calcium carbonates, but not coming back to the chemistry department at the same until 1950. I did not have a chance to go on and study the university. Such a move was quite rare, but he did it to pursue geochemistry of boron. his own interests. This did not make him popular among UBM: What happened to prevent you from studying chemists in Japan, but he gained an international reputation boron? for his interdisciplinary scholarship. Incidentally, Minami MH: In principle, nothing prevented me from it, except was a Roman Catholic and a devotee of Esperanto, but he did that during the war the arrangements to perform that work not succeed in interesting any of his students in Esperanto. were not available to us. UBM: Given his own interest in meteorites, if Professor UBM: From the dates you mentioned earlier, I gather that Minami, as your teacher—or “mentor” as we might now call the war began the year before you entered graduate school. him—did not encourage you to study them, what research MH: That’s right. topic did he assign to you? UBM: Did the bombing of Pearl Harbor come as the MH: He recommended that I start with the geochemistry complete surprise to you in Japan that it did to us? of strontium. At that time, I had become interested in the MH: Yes, it certainly did. No civilians knew of plans for papers on biogeochemistry by Professor V. I. Vernadsky in any such a thing. Russia and was strongly influenced by them, so I asked for a UBM: And it was such a stunning success—it nearly more biologically oriented theme. Professor Minami did not wiped out the U.S. Pacific fleet! I would think there must have entirely reject my idea, but he suggested that I should first try been great celebrations in Japan. studying strontium and then continue on with the MH: That’s true. We did celebrate when we heard the geochemistry of boron, which V. M. Goldschmidt had news. Oral histories in meteoritics and planetary science: XI. Masatake Honda A179 UBM: What did you do next, after you finished your same laboratory. Marriage between people in the same room work on strontium? in a laboratory has become quite popular since then. Besides MH: I began serving as a technical officer in the Japanese being a good chemist, my wife, Nobuko, is a highly talented Imperial Navy. During my tour of duty, I had my first chance painter. to study about ion exchange resins. Back then, ion exchange UBM: I have seen some of her water-color paintings of was a new topic in chemistry and I tried to apply the technique flowers. They are exquisite. for separating various elements. My idea was sound and it led MH: I quite agree. directly to what later would become the subject for my Ph.D. UBM: What were you working on at Mitsui? thesis. MH: I was doing mostly spectrographic analyses, as a UBM: Was the topic of ion exchange assigned to you by job.

Load more