Arthur F. Davidsen, professor of Physics and Astronomy at the Johns Hopkins University, passed away unexpectedly on 19 July 2001, from complications related to a lung disorder. At 57, he was still actively involved in teaching and research, and continued to play a key role in administering on-going projects and pursuing new opportunities.
Davidsen was born on 26 May 1944 in Freeport, NY on Long Island. The youngest child of Norwegian immigrants, he attended Princeton University, graduating in 1966. Although accepted into graduate school at Berkeley, he first served five years as a Naval officer, initially on a destroyer and then at the Naval Research Laboratory where, through his association with Herbert Friedman, he was introduced to space astronomy. Davidsen received his PhD in 1975 from Berkeley and came directly to Johns Hopkins as an assistant professor. Less than two years later, in April 1977, Davidsen led a successful sounding rocket campaign to obtain the far ultraviolet spectrum of the quasar 3C 273, an effort that resulted in his being awarded the American Astronomical Society's Helen B. Warner prize in 1979.
This and other sounding rocket successes led to a bold proposal to NASA in 1978 to build and fly a meter-class space shuttle-borne far ultraviolet telescope as part of NASA's Spacelab concept. This proposal was accepted in 1979, a year and a half before the space shuttle launched for the first time, and set the stage for a major thrust of Davidsen's career, the Hopkins Ultraviolet Telescope (HUT) project. Although it suffered a number of setbacks, including the delays due to the Challenger disaster, HUT ultimately flew two successful missions on the space shuttle, Astro-l in December 1990 and Astro-2 in March 1995. During the latter mission, Davidsen was able to make a definitive measurement of the intergalactic medium by using a high redshift quasar as a background source, carefully analyzing the redshifted He II Lyman α forest and searching for the He II Gunn-Peterson effect. This work, and the subsequent theoretical modeling of the result, will probably stand as his most significant of many scientific contributions.
Davidsen is widely credited with having been a major force behind the AURA/JHU effort that landed the Space Telescope Science Institute on the Hopkins campus, an occurrence that had a large part in the development of the astrophysics program at Johns Hopkins. He was also founding director of the Center for Astrophysical Sciences at Johns Hopkins, and formulated the administrative support structure that permitted astrophysics to blossom at Johns Hopkins. Even in the down time after the Challenger incident, Davidsen kept Hopkins on the map by chairing the Local Organizing Committee for the IAU General Assembly in Baltimore in 1988. It is safe to say that the $35 million Bloomberg Center for Physics and Astronomy, which opened in 1990 across the street from the Space Telescope Science Institute, would not have become a reality without his leadership and foresight.
Davidsen's leadership has been felt throughout the community by way of his dedicated work on many panels, boards, and committees of NASA, NSF, AURA, NRC, and AAS over the years. He served as interim dean of the Krieger School of Arts and Sciences at Hopkins in 1997, and had most recently chaired the Advisory Committee of the Sloan Digital Sky Survey project. Amongst many honors, he was a fellow of the American Institute for the Advancement of Science and the American Physical Society. In addition to being the Principal Investigator of HUT, he was a Co-Investigator on the Hubble Space Telescope Faint Object Spectrograph team and many other instrumentation projects over the years.
At the time of his death, he was actively participating in several research projects involving his scientific passions, the intergalactic medium and Active Galactic Nuclei, using data from the Far Ultraviolet Spectroscopic Explorer satellite as well as preparing to teach classes this fall. Davidsen was a teacher on many levels, and was as comfortable in an introductory course as he was overseeing many PhD theses or mentoring and coaching members of his own carefully crafted HUT team, many of whom have gone on to positions of great responsibility in subsequent projects.
While we will greatly miss Arthur's continued presence and leadership, his legacy is clear. We mourn his untimely passing even as we celebrate his exemplary life as a scientist, teacher, colleague, mentor, friend, and leader in the truest sense of the word.
Photograph by Lightner Photography