Named in memory of Ira S. Bowen (1898–1973), whose investigation of the ultraviolet spectra of highly ionized atoms led to his identification of the mysterious ‘nebulium’ spectral lines of gaseous nebulae as forbidden lines of ionized oxygen and nitrogen; he soon explained most of the spectral lines of gaseous nebulae. As director of the Mount Wilson and Palomar Observatories from 1948 to 1964 he oversaw the completion of the 5-m reflector and 1.2-m Schmidt and designed many of their instruments, including a novel spectrograph. He also initiated the baking of photographic plates to improve their sensitivity. (M 16245) _ _.