University of Arizona Lunar and Planetary Laboratory Professor Emeritus Uwe Fink passed away on 18 January 2026 after a brief illness. During his long career, Fink carried out laboratory spectroscopy and observations on all of the planets in the solar system and their satellites as well as asteroids and comets. During this golden age of planetary exploration, he developed and built instruments for laboratory use and telescopic observations using the technique of Fourier spectroscopy and later CCD spectroscopy. The laboratory work identified the opacity spectra of molecules that could then be searched for spectroscopically. He was the first to employ CCDs for planetary spectroscopy, enabling him to obtain the first good visible and near IR spectrum of Pluto. Highlights include the discovery of the icy composition of Saturn’s rings, measurements of ices on the Galilean satellites, and an early measurement of water vapor in the atmosphere of Venus from airborne spectra. A major advance was the first detection (in collaboration with Harold Larson) of water vapor in the atmosphere of Jupiter, particularly relevant today in the context of measurements of the atmospheric compositions of extrasolar giant planets. Also important was their first detection of the disequilibrium species GeH4 (germane, the germanium analog of methane) and PH3 (phosphine) in the atmosphere of Jupiter. His spectra of Jupiter and molecular detections are still often cited in the modern brown dwarf and extrasolar giant planet literature. Later in his career he carried out extensive observations of comets.
