Dr. Eldon Earl Ferguson, an eminent physicist and atmospheric scientist, died in Paris on April 26, 2017, at the age of 91. He and his research group at the National Bureau of Standards in Boulder, Colorado developed the flowing afterglow technique to study the chemistry and physics of ionized gases. Over a twenty-year period, they measured the rate constants of several hundred ion-molecule reactions, many as a function of tem-perature and energy; their pioneering studies allowed a comprehensive characterization of the ion chemistry of the earth’s atmosphere. In an Account and Perspective article published in the Journal of the American Society for Mass Spectrometry, El-don provided a personal history of the early development of the flowing afterglow technique (Ferguson, E.E. J. Am. Soc. Mass Spectrom. 3, 479-486 (1992)). Many scientists throughout the world have used and adapted the instrumentation to ex-plore a wide array of applications including physical organic chemistry, thermochemical measurements, astrochemistry, medical analysis and diagnosis, and trace gas detection. A fuller description of Eldon’s remarkable life and outstand-ing scientific contributions is provided in an obituary in Physics Today.
- Veronica Bierbaum, University of Colorado Boulder.