Dale Flint Dickinson of Menlo Park, California, passed away on 23 July 2017 after a long battle with Lewy Body Dementia. Dale was born on 11 October 1933 in Galveston, Texas, the only child of Andrew Flint Dickinson and Leona Minnie Warner Dickinson. He grew up in Galveston and graduated from Ball High School in 1950. He then spent one year at Schreiner University before transferring to the University of Texas at Austin. He graduated in 1955 with a degree in Petroleum Engineering. While at the University of Texas, Dale decided that mathematics and physics were his true passions. He entered the physics graduate program at the University of California Berkeley but was quickly drafted. Dale spent 2 years in the US Navy as an electronics technician, and then re-enrolled at Berkeley in 1957. He completed his Ph.D. in nuclear physics in 1964 and spent the next year traveling around the world with his first wife, Leslie Bryan.
Dale's early interest in astronomy was re-kindled after he returned to Berkeley, and in 1967 he accepted a position with the radio astronomy group at the Smithsonian Astrophysical Observatory (SAO) in Cambridge, Massachusetts. This was five years before the formation of the Harvard-Smithsonian Center for Astrophysics, but Professor A. E. Lilley of Harvard University was in the process of forming a research group with members from both Harvard College Observatory and SAO in the nascent field of molecular spectroscopy in radio astronomy. The group, which flourished in the 1970s, consisted of Dale, Carl Gottlieb, Marvin Litvak, Jim Moran, Hayes Penfield, Harry Radford, Mark Reid, and others. Dale participated in the discovery of many molecular transitions including those of methyl alcohol (CH3OH), silicon sulfide (SiS), cyanoacetylene (HC3N) and other molecules. Those were heady times that gave birth to the field of astrochemistry.
Dale’s first marriage ended in divorce in 1976. He met Ann Dinger, his second wife, also an astronomer, in 1973, at a meeting of the American Astronomical Society. They were married 26 November 1977, in Wellesley, Massachusetts. Over the following decade Dale and Ann co-authored a number of papers, mostly on cosmic masers. Dale left SAO in 1977 and they spent a year as visiting professors at Williams College in Williamstown, Massachusetts, and then moved to Pasadena, California, where Dale held a National Research Council Fellowship at the Jet Propulsion Laboratory. Dale then worked at the Applied Technology Division of Litton Industries in the San Francisco area for 16 months before moving to Lockheed's Palo Alto Research Lab in 1984. Dale obtained various grants to continue his astronomical research while working for Lockheed. He retired in 2000, and then worked part-time for Polar Magnetics Corporation until 2004.
Dale was an expert in the subject of maser emission in the envelopes of evolved stars. Working with Mark Reid he solved a longstanding riddle about the true velocities of these stars. They established that the stellar velocity was not the velocity associated with the optical emission lines, as long assumed, but was marked by the mean velocity of the double-peaked OH maser spectrum. This led to the proper understanding of the kinematics traced by maser molecules in the envelopes of these stars. He also worked with Eric Chaisson, a Harvard graduate student at the time, to show that the stellar period and velocity separation of the maser peaks are strongly correlated. He also pursued a completely different line of research into the nature of Markarian galaxies, primarily with his long-term colleague, Gabriel Kojoian. His last scientific paper, published on this topic, appeared in 1995.
Dale was a kind and gentle man, widely known for his calm demeanor, unflappable nature and offbeat sense of humor. He often included humorous comments in his professional papers. In one paper based on observations at Haystack Observatory in Westford Massachusetts, he noted "The experiment was performed on 1974 May 23-24 in conditions of intermittent rain, fog, drizzle, and heavy overcast. In New England this is known as spring." Helmut Abt, the Astrophysical Journal editor, laughed but told Dale to remove the second sentence. However, a footnote citing the Green Bank 300-foot telescope as “deceased” did make it past the editors and referees.
Dale authored 66 articles in refereed journals and 11 in general science magazines including an article on cosmic masers for Scientific American in 1978. Dale also taught several courses for the Harvard Astronomy Department and was involved in research projects with Harvard graduate students.
Dale was a serious and highly accomplished skier. He was a ski instructor for many years and specialized in teaching young people to ski. Skiing magazine published his column, "A Ski Child's Mother Goose," in 1988. His enjoyment of skiing was picked up by his whole family.
Dale loved to travel the world and pepper his friends with postcards from exotic locations. He was happiest in the mountains, either hiking or skiing. He and Ann visited places as diverse as Iceland, Tibet, Turkey, and Tierra del Fuego. Dale also trekked in Nepal and India, as well as on Baffin Island. He was well known for his penchant to take the scenic route during his travels (aka “doodling around”).
Dale is survived by his wife Ann, 2 daughters from his first marriage, Kelly and Tracy, and two sons from his second, Geoffrey and Derek, as well as 4 grandchildren, Ava, Alexander, Harlan, and Marlow.
Affiliations: Smithsonian Astrophysical Observatory, Williams College, JPL, Applied Technology (Division of Litton Industries), Lockheed-Palo Alto Research Lab.
Obituary written by: Ann Dinger Dickinson and James M. Moran.
Photo from family archives, 2012