Born at Weymouth, Dorset, Moseley was educated first at Eton and then at Trinity College, Oxford. Immediately following graduation, he accepted a post as lecturer in physics in Ernest Rutherford's laboratory at the University of Manchester, where he remained until wartime.
Henry Moseley's first research concerned radioactivity. Then he began his spectacular research on the X-ray spectra of the elements. Moseley revealed the structure of the electron rings in almost all atoms so that the X-ray spectra of the elements could be arranged in a continuing series. Moseley's work made it possible to identify elements by continuously ordered numbers. His discovery was a vital contribution to the understanding of atomic structure.