Mössbauer, Rudolf Ludwig, 1929–, German physicist, Ph.D. Max Planck Institute for Medical Research, Heidelberg, Germany, 1957. Mössbauer was a professor at the California Institute of Technology from 1961 to 1964, when he joined the faculty at the Technical Univ. of Munich. He was a co-recipient, with Robert Hofstadter, of the 1961 Nobel Prize in Physics for his research on the emission and absorption of gamma radiation by atomic nuclei. He discovered the Mössbauer effect, in which nuclei that are in a crystalline lattice, which prevents the nuclei from recoiling, can emit and absorb gamma radiation resonantly. It allows highly precise measurements of frequency and has been applied to problems ranging from investigations on the surface of Mars to studies of corrosion.