Francis William Aston

Francis William Aston (1877-1945), British physicist and Nobel laureate, born in Harborne, Birmingham, England, and educated at Malvern College, University of Birmingham, and Trinity College, University of Cambridge. Aston built (1919) the first mass spectrometer and with it showed that many elements are mixtures of two or more isotopes with slightly different atomic weights. Aston's work, which was accurate to 0.1 percent, was the first quantitative study applicable to all the elements. For his discoveries he received many honors, including the Nobel Prize in chemistry in 1922. He wrote Isotopes (1922) and Mass-Spectra and Isotopes (1933).