German physicist · 1873–1939
Otto Berg
Otto Berg was the X-ray specialist in the team that discovered rhenium in 1925.
How Rhenium was found
X-ray spectroscopy, developed by Henry Moseley a decade earlier, identifies elements by the precise X-rays their atoms emit, which depend on their atomic number. Berg, working at the Siemens & Halske laboratories, took the X-ray spectra of the samples Ida Tacke and Walter Noddack prepared.
His measurements showed lines that could only come from element 75. The team’s claim to element 43 rested on weaker lines that could not be reproduced.
Shared the credit
The discovery is credited jointly to these scientists.
Life and career
Born 1873 · Died 1939
Berg was born in Berlin and spent much of his career in industrial research at Siemens & Halske, working on X-ray tubes and spectroscopy.
Discovered in the same era
Other elements identified within ten years of 1925.