Rudolf Ludwig Mössbauer was a German physicist best known for his 1957 discovery of 'recoilless nuclear resonance fluorescence', for which he was awarded the 1961 Nobel Prize in Physics. This effect, called the Mössbauer effect, is the basis for Mössbauer spectroscopy.

Mössbauer spectroscopy is a spectroscopic technique based on the Mössbauer effect. This effect, discovered by Rudolf Mössbauer in 1958, consists of the nearly recoil-free emission and absorption of nuclear gamma rays in solids. The consequent nuclear spectroscopy method is exquisitely sensitive to small changes in the chemical environment of certain nuclei.