Henry Moseley, killed on the field of honor in 1915 at the age of 27, did not get the Nobel Prize. He would have deserved it by the importance and variety of his contributions including the empirical law connecting the X-spectrum of an element to its atomic number.
From 1914 Manne Siegbahn studied X-ray spectroscopy with Rydberg at Lund University. A brilliant engineer, he greatly improved the resolution of the measurements, resulting in a classification and mapping of the Moseley spectra. In 1922 he became a professor at the University of Uppsala. He published his results in 1923 under the title Spektroskopie der Röntgenstrahlen.
In 1924 the Nobel Committee failed to appoint a laureate in physics. In 1925 this prize is awarded retroactively to Siegbahn.
Kai Siegbahn follows in the steps of his father. Using the photoelectric emission, he obtains high precision measurements of the energy levels in the atoms. He shares the Nobel Prize in Physics in 1981 with two specialists in laser spectroscopy.
The Nobel medals and diplomas from Manne and Kai Siegbahn will be sold together by Sotheby's in London on July 9, lot 400 estimated £ 150K.